Some Targets, not just in my area of the country, seem to sell Mobil 1 at much lower prices than other Target locations. My local Target actually was selling the Tri-Synthetic version for < $3 a quart for a while. The $3.38 price is their 'regular' price - it is stamped that way on the placard that's stuck on the front of the shelf. It has been that price for several weeks.
Remember that line in "As Good as It Gets" were Jack Nicholson answers the question, how can he understand women so well in his books? He says I take a man, subtract all reason, add emotional volatility, etc. in his rant.
I got to thinking about motor oils the same way and came up with these thoughts:
Motor oil is like stationery equipment oil - oil that keeps gears lubricated so the wheels of industry don't grind to a halt.
Then, you heat the stationery equipment up to about 400 degrees in the hot spots, otherwise about 200 degrees; you add extreme shear forces (think: pistons slicing the oil in the cylinder walls); then you add extreme bearing surface pressures (think: power stroke down against the crankshaft, and pistons and rings pushed against cylinder walls); then you add chemical contamination (think: piston blow by, with byproducts of partial combustion, soot, unburned gas and, in the morning, a fair amount of water vapor).
When I got through thinking about it, I couldn't imagine a more horrible environment for something as simple as an oil. Actually, the crankcase in a 4-stroke engine is probably only marginally cleaner than in a 2-stroke engine, in terms of combustion by products - that's why one of the first smog devices on cars in the '60s was to recycle crankcase fumes back into the air intake system to be burned in the combustion chamber.
No wonder the popular wisdom is that there is not that much "oil" in motor oil - instead it has a lot of additives, by volume, to do the "non-lubricating" part of its job (and also additives to reduce wear and friction in the high pressure environment).
So the bottom line is, the raw, naked "oil" part of synthetic oil might be a lot better than dino oil, because it is manufactured to hit a narrow range of specs, rather than "distilled" down to a broader spec range and then beefed up with shear stabilizers, viscoscity improvers, volatility controllers - but the "additive" part of synthetic oil is probably not much, if any, better in synthetic oil. Therefore I favor 3,000 mile oil changes in my car - not to replace the "oil" but to replace the "additives."
Maybe if you are a mild day to day driver with easy, mid-range to long range commutes (but little stop and go), then longer oil change intervals with synthetic are probably ok, because your oil isn't stressed by "hard driving" or "short trips" (or "towing," or "stop and go driving", which complete the list of "severe" circumstances calling for short oil change intervals in most owner's manuals) but I don't think I would go beyond what manufacturers recommend for their "normal" drain intervals - which, in the case of one of the Big Three, Ford, is only 5,000 miles (they say 5,000 regular, 3,000 severe). In other words, in a nutshell, I think the car manufacturers, so satisfy public pressure to reduce resource consumption and to increase the "low maintenance" perception of their vehicles (and because "oil changes" at dealer seem to turn into $70-$150 "minor services"), have upped the oil change interval way too optimistically. Rule of thumb - follow the "severe" cycle even if you don't think you fall into that service category.
Also, there is the whole issue of the real useful life of oil filters. I am dubious a $2 filter can last even 5,000 miles without a substantially increased risk of failure,uch less 7,500 or 10,000 miles (Fram sort of acknowledges the fact by having an extended use filter in its line, for "oil changes in excess of 3,000 miles", while telling us on their regular line that it "meets manufacturer's specs" which should be 7,500 most cars, 10,000 on Hondas and VW's.)
BTW, short trips are especially hard on the additive pack in motor oil, synthetic or conventional, because short trips load up the oil with contaminants which are predominantly the product of short trips, and the engine doesn't run hot enough long enough to purge some of those contaminants - especially the water- out of the oil.
Now as to conventional vs. synthetic oils, I think it really depends on driving habits and conditions, and not on "oil longevity." The first issue is to decide to change oil frequently. The second issue is to decide how rough you are on your car, what the typical rpm's of your car are, and whether any of its drivers make jack rabbit starts and high speed freeway runs (think: commuter) before the car is warmed up and the oil is at its operating temperature.
A cold car is a car prone to injury, just like a person. That is why it's hard to argue with the "5" part of the oil spec for most drivers. True, auto manufacturers probably went to 5W-30 oils (instead of 10W-30) to save gas used during the warm-up part of the typical person's drive (the EPA gas mileage cycle is a relatively short trip), but that thinner oil can also lube better if you get on the gas or start moving fast before the engine is warmed up (on this issue of controlling rev's during warm up, some BMW's actually lower the redline on the tachometer during the warmup period).
Lower cold start viscoscity (the first part of the oil designation, the "5W-" or "10-W" part) is also very good in cooler or freezing weather - the benefits are multiplied.
The bad part of a lower cold flow viscoscity is that the chemicals used to improve viscoscity - to "trick" the oil into behaving like a thin "single weight" oil when it is cold, but into staying thick like a much heavier, thick "single weight" oil at operating temperature - is that these chemicals rely on a complex molecule that is very long, which unfolds and contracts and thereby affects the flow-ability of the oil. It is as if you, as a person, reach out your arms to hold a bunch of balloons from wandering off. Since the molecules are so extended, they can be "sliced" or "sheared" by the close tolerance moving parts in the car's engine - imagine your long gangly arms getting caught in a revolving door. Once the viscoscity molecules are sheared, the viscosity of the oil is severely impaired - it's no longer very "multi" viscoscity. This is wear full synthetic oil shines - it isn't so dependent on viscoscity enhancing molecules. (The Chevron site says 5-40, a common European viscoscity range specifed for BMW, VW, and Mercedes, is not recommended in conventional oils, only in synthetics.)
There is another way to deal with viscosity loss, and that is to choose an oil with a narrower viscoscity range, and/or one that is basically thicker to begin with. Thus 20-50 oil has less viscosity to give up (although its hell on cold starts), and also has a very narrow range - 2.5:1. 5-20, on the other hand, is pretty thin at operating temperatures and therefore a much smaller margin for error - you are already starting pretty low, at 20 weght at operating temperature, and as you lose viscoscity it rapidly downhill from there.
10W-30 is preferred for hard driving because the range is only 3:1 vs. 4:1 for 5W-20 and 6:1 for 5W-30. Also
10W-30 is preferred for hard driving because the range is only 3:1 vs. 4:1 for 5W-20 and 6:1 for 5W-30. Also it runs at 30 weight at operating temperature, which is much better than 50 weight or 40 weight oil (remember 10-40? it lost out to fuel economy concerns). But it is significantly thicker than 20 weight at operating temperature. Admittedly 20 weight at operating temperature in a car engine designed with minimal "hot spots" is probably ok, but what is the margin for error and degradation?
Since I run my car hard, but only when it is fully warmed up, and live in a temperate climate, I am probably better off with a 10W-30 range, at least in conventional oil, to provide consistent protection on high speed interstate runs and when rev'ing to the redline (On the Dodge Neon, Chrysler indicates either 5-30 or 10-30 are appropriate choices). In the winter or if I am impatient in the morning when first getting on the freeway, 5-30 conventional might be an option, or 5-30 full synthetic solves the quandary - cold start protection, or freeway protection.
Keep in mind that viscoscity degradation takes place over time, so that is another reason for 3,000 mile oil changes - to keep the oil within spec. Once again, degradation is slower with synthetic oils.
The second issue to consider in conventional vs. synthetic is, how "hard" do you drive? I mean, how much do you load up your engine, how high to you rev? Engine load can be heavy due to a variety of factors - passenger and cargo load, pulling a trailer, lugging the engine instead of downshifting (throttle is pushed down relatively far, but engine revs are low), driving uphill in the mountains, driving extremely high speeds (wind resistance). A turbo is, ipso facto, high load, because it is pushing more horsepower out of a lower displacement. VW in fact requires full synthetic oils on its turbo models.
So it's really a battle of the marketplace:
Synthetic oils sell for more than they are worth, because they are a premium item with a limited marketplace and its purchasers are less price conscious.
Car makers need better CAFE (corporate average fuel economy) figures so they will push any oil that looks good for fuel economy, and hope consumers will opt out of the designated oil later (thus 5-20 oil for Ford, which needs CAFE, and Honda/Acura which thrives on a "green" image). (Meanwhile the oil VW's "really" need is supposed to be 5-40, which Chevron thinks should be full synthetic due to its extreme range; but VW will accept 5-30 in America - VW cares less about fuel economy, and wants cold start protection, with its side benefit of better cold running fuel economy, but wants operating temperature thickness - hence the "40") (Dodge Neon, both 1999 and 2002, say either 5-30 or 10-30 are ok, provided they are "fuel efficient" - the Neon has a hard working engine with relatively high output.) (Corvettes want Mobil 1. Fuel economy is a foregone concern.)
Car manufacturers want the appearance of low maintenance, but Ford isn't willing to press this beyond 5,000 miles. Honda, once again "green," pushes their intervals to 10,000 miles. VW pushes to 10,000 miles, but they consume so much oil between intervals it becomes a defacto oil change (this is not a jibe, I own one and the oil consumption is the truth - a quart every 1,500 miles, or more often on some cars, up to a quart every 1,000 miles).
Oil companies want to sell oil. Duh. But they also don't want premature engine wear blamed on them. Quaker State, now owned by Pennzoil, still has a promotional "250,000 mile" warranty if you will document your oil use, and change at least every 4,000 miles. (So is 4,000 miles the magic number? It is the same number, by the way, for their dino and synthetic lines.)
What will I run in my cars? Since the VW chews through oil, I am switching to dino oil, and will narrow the viscoscity range from 5-30 to 10-30 for some added viscocity range protection. I think the new SL/GF-3 spec is pretty good. Then when I add quarts of oil in between changes I won't moan. I will change every 3,000 miles to make up for the more rapid degradation of conventional motor oil. I will take my chances on bearing protection and cylinder wall scuffing resulting from high speed driving, hoping that millions of miles driven in Europe with conventional oils means VW's 2.0 liter design is sound, even though it rev's 4,000 rpm at 80 mph.
In the Honda, I will run 5-20 to protect the warranty, but change at 3,000 miles to keep the oil in top condition (less chance to degrade). When the warranty expires, I will switch to 10-30 or at least 5-30, and possibly run full synthetic (the Honda only has a 3.5 quart vs. 4.5 quart capacity on the VW, so there is less oil to absorb abuse). If I run full synthetic, I will extend to 5,000 mile intervals on the Honda to save money.
I am running STP oil filters from Autozone, manufactured by Champion and rated highly on the web. For the VW, I use Bosch right before I go in for dealer service, otherwise STP. I don't let the dealer change the oil, since they use Castrol GTX (not bad, but I prefer Mobil Clean Blend, which is more compatible with Mobil 1 if I switch back; also Mobil Clean Blend has the CF light duty diesel rating, it can hold a lot of dirt).
Well, those are my thoughts. Pity on your employer if you read this long post at work!
You make a good argument for oil analysis for conventional oil. TBN was measured at 15.5 in an above synthetic oil analysis. Most conventional TBN starts at 5-7.
for micweb #5165 and #5166. Let me know if there is actually any useful information in there. I read about 2 paragraphs and saw no information that hasn't been written here before. His "stepping into the engine pretending to be an oil molecule" was pretty funny though.
I have an Infiniti G35. The owner's manual recommends "mineral-based" oils. Another G35 owner has asked the service dept. of a dealership about this, and their response was that some Japanese engines come with silicon gaskets/seals, and synthetic oils can break down silicon seals over time.
I'm quite sure someone here has an opinion on that subject, and I'd like to hear it. I'd rather run synthetic in it to take better care of it, unless I'd actually be harming it instead.
Most cars don't bite the big one because of oil failure. I've only had three engine failures in 28+ vehicles none oil related. Something else usually creeps up to make the car undrivable before the engine craps out. Trying to make the engine last for 400K on a 250K car is overkill.
Most cars will do 4K miles easily on just about any SL oil--maybe not some Toyotas, don't know about your VW. I do like 10W30. 5W30 will shear down after 3000 miles but I don't know if there's any proof that it's dangerous. Most 5W20 has enough moly to stay in grade-- don't know if I'd feel comfortable taking a Honda to 10W30 after the warranty period is up. Don't spend enough time on the Edmunds 5W20 threads to form an opinion, but most 5W20 UOA's on Bobistheoilguy seem to be holding up remarkably well.
I change my oil at 4K intervals. If I wanted to go to synthetic I'd probably feel safe at stretching things out to the non-severe driving schedule for my car (Elantra 7500 miles). Would probably do this even with a good group III oil, definitely with a group IV.
I use a SuperTech filter same as your STP. I'd have no trouble pushing it to the 7500 mile mark if I used a synthetic.
Any of you guys used this additive that claims to clean the engine from deposits and sludge...etc..Does it really works? http://www.auto-rx.com/index.html
I just purchased a new 2003 Saab 9-3. It's the first car I've owned which uses synthetic oil (0W30 Saab brand). The manual recommends Saab or Mobil oils, but I'm being told by Saab USA and the dealer to use only the Saab product to top it off if required. My previous experience with dino oils says that I can mix brands as long as the specifications match. Is this not the case with synthetic products?
I skimmed it, but I will take exception to Myth #8. I believe Mazda specifically warns/warned against Synthetic oil in rotary engines. If that is the case, I'm sure the warranty is voided if you did use a synthetic in a rotary with such a warning from the carmaker.
Can someone tell me which brand has better OIL, AIR and FUEL filter and why. I approaching the 60K mark and need to replace these. I heard some good things about Purolator PureOne(oil filter) but I also heard that filter is so densely packed that could restrict oil flow? What are your experiences with either brand?
The problem becomes whether or not it makes a difference to you to mix synthetics group 3 (hydro cracked) as in Castrol etc. with (better) group4 synthetics as in Redline, certain Amsoil, Mobil One. Delvac1, etc.
The unknown with SAAB synthetic oil products is unless you know who the vendor is for their oil, you really don't know if it is a (hydro cracked) group 3 or (PAO) group 4. ( you can probably almost count on the fact that it is the hydrocracked synthetic)
On one hand it really doesn't matter. (as long as it meets SL ratings)
But on the other hand, for example, I personally would not mix Mobil One, except in an extreme emergency with hydrocracked synthetic products. Since I do 15k interval oil filter changes, depending on when I added the "mix" I would not do a full 15k oil change if it has been mixed. If I did a 5-7.5k interval I would have NO concerns at all. If I mixed PAO products, (like Mobil One,Delvac1, Redline, Amsoil) again no concern with 15k intervals
You might want to modify that question a little, and look at the brands (plural) that have better filters for automotive applications. Purolator, STP, Supertech, Wix, NAPA, and many other names are all in the BETTER category. I would suggest you post an inquiry in one of the filter discussions, and I'll bet you get good responses.
When you say "Purolator, STP, Supertech, Wix, NAPA, and many other names are all in the BETTER category" does that mean better then OEM filter or just better then the rest of the bunch?
That is a tough question to answer succinctly. Perhaps MOST of the OEM automotive manufacturer filters are in the top echelon I have called "better." There are certain manufacturers of after market filters that just do not produce inferior filters. These often are sold under several brand names, to accommodate retailers who want in-house names or some such. The topic has been investigated at great length in several threads/topics/discussions on filters in Edmunds Car Discussions. You should consider reviewing some of those topics to get a feel for the information.
I just took delivery of a 2003 VW TDI Jetta, a turbo diesel. VW has specified a synthetic oil. It has also recommended 10,000 mile intervals between oil changes.
I wound up going to a truck stop to get Mobil One's diesel sister, synthetic Delvac 1, 5W-40. They speak in different numbers at truck stops. When I asked for Delvac 1, he asked how many cases would I like. (1 case= 4,1 gal containers) So I told him the sump only held a gal and an eighth. He almost busted out. I got a case. It sure takes the better part of a 80 dollar bill
Slightly off topic, but I like the new mileage numbers @ 45/49 mpg. The real world range is between 36-52 mpg.
Call the customer service line for Mobil 1. They make many of the private label synthetic oils for European manufacturers. They may make the Saab oil too.
I spoke with a guy who does oil changes for a living. He said that Castrol has taken the lead in synthetic oil vs. Mobil 1 and that many manufacturers, including Mercedes, Chevrolet and others are switching to Castrol. He mentioned that Mobil 1 could cause bearings and seals to pop out, that the Mobil 1 gets into places it shouldn't be.
Bottom line he said Castrol was the best stuff out there. Any comments? Thanks!
Do NOT use this guy for oil changes. USA formula Castrol is group III and not highly regarded. If the Castrol is the European formula, it is very good. But the stuff about Mobil 1 is garbage.
My car's owner's manual recommends mineral-based oils. Plus, a dealership tech claims that synthetic oils can degrade the silicon seals used in the engine. Does anybody know of anything to the contrary? Thank you.
Yeah, I can just see the old wives spreading disinformation about synthetic oils over a cold one. FYI, the use of synthetics is becoming less and less appealing given the quality of the SL dino oils.
I don't use synthetics, but believe them to be better. Since cars are complex, oil related failures account for a small percentage of reasons for giving up a car--therefore I use dino.
However, did you mean that your owner's manual says to use dino. only? I find that very odd. Could you please copy the verbiage related to the recommendation?
Incidently in line with one of my above latest post about synthetic oil in a VW TDI or turbo diesel, there is an VW TSB that in effect says synthetic oil will be used for subsequent dealer oil products in the TDI. (Read: VW was tired of warranty work on turbo diesels blowing up due to the use of high quality conventional oil.)
I have an I30 and my Infiniti dealer (a very good dealer experience for over five years now) put Mobil 1 in my car (I provided it, of course). If Infiniti recommends mineral based oils, my dealer doesn't subscribe to it. I've talked to several guys at my dealer and they all thought my switch to Mobil 1 was a good move.
SUS VISCOSITY @ 210 ºF 64 55-62 FLASHPOINT IN ºF 415 >365 FUEL % <0.5 <2.0 WATER % 0 <0.05 ANTIFREEZE % 0 0 INSOLUBLES % 0.04 <0.6
LAB COMMENT:Nothing too unusual showed up here. This oil was run quite a bit longer that what we normally see and this is the reason for most of the high wear. The universal averages column shows typical wear from this type of engine after 4,000-5,000 miles on the oil. Lead at 23 ppm shows mildly high bearing wear, though everything else looks okay. The TBN was 3.5 which is low, but not a problem. 2.0 or less is considered a problem. The oil started at 10-11. No fuel or anti-freeze was present. Suggest going 11,000 next oil and resample at that point to monitor.
You obviously used Blackstone and one of my complaints with them is that do not extrapolate the wear metals for those that occur (for the most part) over time (wear for the most part occurs normally over time). Like iron for example. Their univ ave says 12 ppm for 5000 miles in their ave. Well, that would be about 24 ppm for 10,000 miles, your interval. They should do this for most wear metals. So, your iron and lead are slightly elevated but silicon is good so the wear is not coming from dirt. To me this makes their univ ave. confusing and almost worthless.
Ok, my interpretation, excellent results. However, remember that analysis is trend analysis so one sample is extremely hard to interpret. This oil went through the winter so the iron content could be higher due to this. Lead, well, it could be normal for this engine, we just don't know based on one sample. You apparently did not change the filter during the 10,000 but that probably would not make much diff. So, climate, driving conditions, what oil it is, short trips in winter.
This really is a pretty good report, however, I would stay with 10,000 and see what the report looks like after summer driving. If good you have this engine and oil nailed down for the future.
Good results, zoomzoom626, but it would be even better yet, if you changed the filter and oil at 5K. I'll bet that less than half the value of the high numbers was achieved at 5K. That would require two analyses to prove, though.
Good results, zoomzoom626, but it would be even better yet, if you changed the filter and oil at 5K. I'll bet that less than half the value of the high numbers was achieved at 5K. That would require two analyses to prove, though.
Sure, why not change it every 500 and see just about no wear. the issue is not wear or ppm it is how much wear/mile as wear must occur, it cannot be prevented with todays technology. There is no point to getting 1 ppm in 500 miles or 10 ppm in 5000. The same amount of wear has occurred it just looks better at 500 miles. Now, if you could get .5 ppm in 500 miles by changin oil or conditions then an improvement. There is no proof that more wear occurs in an engine with 20 ppm of iron as opposed to 10 ppm of iron. The particles themself are too small to cause additional wear.
It is reasonable to consider the possibility that the rate of wear rises as the miles of use of the oil increases. "...the issue is not wear or ppm it is how much wear/mile as wear must occur..." Better look at the foul you're committing against fundamental logic here, armtdm.
Am I the only one who thinks the Mobil1 thickened? Yes, it's still within the range of a 30 weight oil, but it starts out lower than 64. Why did it thicken? I think some may think that since it didn't thick beyond what a 30 weight should be that it's ok. But I think that runny oil plus thickening goo doesn't equal slightly thicker oil, it equals thin oil with goo. Does this make sense?
I don't think it's thickened very much at all, esp. considering 10k. It starts out as a very thin 30w and is still very much on the lower end of a 30w. A 10k interval looks good for this oil in this unit.
As the above poster stated: "It is reasonable to consider the possibility that the rate of wear rises as the miles of use of the oil increases."
yes, but if the wear rate is the same the oil is doing its job. The key is to determine when the oil has used up its' aditive package and the wear rate is about to increase. To play that safe change every 3000 miles or use oil analysis to peg the point that the oil is no longer good and go with that.
These are the results that I got from driving trough what was unusually cold winter in DC and it seams that oil held up pretty good. Now I have Mobil 1 10W-30 in and I'm curious what will summer heat do to it. Does the weather/outside temperature plays a big role in how long the additive package lasts? If so wouldn't be reasonable to assume that given the same conditions AMSOIL 5W-30 series 3000(for diesel engine) which has much stronger additive package would last longer then Mobil 1?
Which I believe indicates how much additive is left in oil. Blackstone said that "TBN was low 3.5,but not a problem. 2.0 or less is considered a problem".What I would like to know is what is the TBN number that is good indicator that additive package is gone and it is time for a change. I understood that oil will keep much longer if you could just replenish additives?
TBN is an indicator of the oils ability to control acid buildup. The consensus seems to be that the oil needs to be changed when the TBN has reached 50% of its original value or 2. Now the 50% figure is obviously more conservative when dealing with synthetics that start out in the 10-12 TBN range whereas the dino oils of years ago were in the 5-6 TBN range. Thus, should an oil with a TBN of 12 initially that now has a value of 4 be changed??? Depends. Did this drop occur very quickly (few miles) or has it been 10,000 miles. Oil Analysis is an art not a science!
As to the Amsoil Series 3000, yes would do better and cold climates mean that there is usually more fuel in the oil due to short trips where the oil does not heat up and burn the fuel off *created by idling a lot and short trips) and condensation is also possible and can result in slightly elevated iron numbers in the analysis.
In fact there is one oil that, based upon analysis, lasts forever the company just has you replenish the additives which they sell separately from the oil.. I forget the name off the top.
My 2001 F150 V8 has 34,000miles. I had been using Valvoline 5w30 and 100 miles ago switched to Mobil 1 5w30. Now when my engine is cold and I start it up I notice some blue smoke that I never noticed before. I know it is from Mobil 1 does anyone have an idea what is going on and if I should switch back to non synthetic? This is not a good feeling. Ken from Michigan
Comments
Also there were no deals on any of their oil products. So, I guess it's a local discretion decision.
With Wally infrequently having their 5qt jugs of M1, it would be great to have a second source at bargain rates.
I got to thinking about motor oils the same way and came up with these thoughts:
Motor oil is like stationery equipment oil - oil that keeps gears lubricated so the wheels of industry don't grind to a halt.
Then, you heat the stationery equipment up to about 400 degrees in the hot spots, otherwise about 200 degrees; you add extreme shear forces (think: pistons slicing the oil in the cylinder walls); then you add extreme bearing surface pressures (think: power stroke down against the crankshaft, and pistons and rings pushed against cylinder walls); then you add chemical contamination (think: piston blow by, with byproducts of partial combustion, soot, unburned gas and, in the morning, a fair amount of water vapor).
When I got through thinking about it, I couldn't imagine a more horrible environment for something as simple as an oil. Actually, the crankcase in a 4-stroke engine is probably only marginally cleaner than in a 2-stroke engine, in terms of combustion by products - that's why one of the first smog devices on cars in the '60s was to recycle crankcase fumes back into the air intake system to be burned in the combustion chamber.
No wonder the popular wisdom is that there is not that much "oil" in motor oil - instead it has a lot of additives, by volume, to do the "non-lubricating" part of its job (and also additives to reduce wear and friction in the high pressure environment).
So the bottom line is, the raw, naked "oil" part of synthetic oil might be a lot better than dino oil, because it is manufactured to hit a narrow range of specs, rather than "distilled" down to a broader spec range and then beefed up with shear stabilizers, viscoscity improvers, volatility controllers - but the "additive" part of synthetic oil is probably not much, if any, better in synthetic oil. Therefore I favor 3,000 mile oil changes in my car - not to replace the "oil" but to replace the "additives."
Maybe if you are a mild day to day driver with easy, mid-range to long range commutes (but little stop and go), then longer oil change intervals with synthetic are probably ok, because your oil isn't stressed by "hard driving" or "short trips" (or "towing," or "stop and go driving", which complete the list of "severe" circumstances calling for short oil change intervals in most owner's manuals) but I don't think I would go beyond what manufacturers recommend for their "normal" drain intervals - which, in the case of one of the Big Three, Ford, is only 5,000 miles (they say 5,000 regular, 3,000 severe). In other words, in a nutshell, I think the car manufacturers, so satisfy public pressure to reduce resource consumption and to increase the "low maintenance" perception of their vehicles (and because "oil changes" at dealer seem to turn into $70-$150 "minor services"), have upped the oil change interval way too optimistically. Rule of thumb - follow the "severe" cycle even if you don't think you fall into that service category.
Also, there is the whole issue of the real useful life of oil filters. I am dubious a $2 filter can last even 5,000 miles without a substantially increased risk of failure,uch less 7,500 or 10,000 miles (Fram sort of acknowledges the fact by having an extended use filter in its line, for "oil changes in excess of 3,000 miles", while telling us on their regular line that it "meets manufacturer's specs" which should be 7,500 most cars, 10,000 on Hondas and VW's.)
BTW, short trips are especially hard on the additive pack in motor oil, synthetic or conventional, because short trips load up the oil with contaminants which are predominantly the product of short trips, and the engine doesn't run hot enough long enough to purge some of those contaminants - especially the water- out of the oil.
Now as to conventional vs. synthetic oils, I think it really depends on driving habits and conditions, and not on "oil longevity." The first issue is to decide to change oil frequently. The second issue is to decide how rough you are on your car, what the typical rpm's of your car are, and whether any of its drivers make jack rabbit starts and high speed freeway runs (think: commuter) before the car is warmed up and the oil is at its operating temperature.
A cold car is a car prone to injury, just like a person. That is why it's hard to argue with the "5" part of the oil spec for most drivers. True, auto manufacturers probably went to 5W-30 oils (instead of 10W-30) to save gas used during the warm-up part of the typical person's drive (the EPA gas mileage cycle is a relatively short trip), but that thinner oil can also lube better if you get on the gas or start moving fast before the engine is warmed up (on this issue of controlling rev's during warm up, some BMW's actually lower the redline on the tachometer during the warmup period).
Lower cold start viscoscity (the first part of the oil designation, the "5W-" or "10-W" part) is also very good in cooler or freezing weather - the benefits are multiplied.
The bad part of a lower cold flow viscoscity is that the chemicals used to improve viscoscity - to "trick" the oil into behaving like a thin "single weight" oil when it is cold, but into staying thick like a much heavier, thick "single weight" oil at operating temperature - is that these chemicals rely on a complex molecule that is very long, which unfolds and contracts and thereby affects the flow-ability of the oil. It is as if you, as a person, reach out your arms to hold a bunch of balloons from wandering off. Since the molecules are so extended, they can be "sliced" or "sheared" by the close tolerance moving parts in the car's engine - imagine your long gangly arms getting caught in a revolving door. Once the viscoscity molecules are sheared, the viscosity of the oil is severely impaired - it's no longer very "multi" viscoscity. This is wear full synthetic oil shines - it isn't so dependent on viscoscity enhancing molecules. (The Chevron site says 5-40, a common European viscoscity range specifed for BMW, VW, and Mercedes, is not recommended in conventional oils, only in synthetics.)
There is another way to deal with viscosity loss, and that is to choose an oil with a narrower viscoscity range, and/or one that is basically thicker to begin with. Thus 20-50 oil has less viscosity to give up (although its hell on cold starts), and also has a very narrow range - 2.5:1. 5-20, on the other hand, is pretty thin at operating temperatures and therefore a much smaller margin for error - you are already starting pretty low, at 20 weght at operating temperature, and as you lose viscoscity it rapidly downhill from there.
10W-30 is preferred for hard driving because the range is only 3:1 vs. 4:1 for 5W-20 and 6:1 for 5W-30. Also
Since I run my car hard, but only when it is fully warmed up, and live in a temperate climate, I am probably better off with a 10W-30 range, at least in conventional oil, to provide consistent protection on high speed interstate runs and when rev'ing to the redline (On the Dodge Neon, Chrysler indicates either 5-30 or 10-30 are appropriate choices). In the winter or if I am impatient in the morning when first getting on the freeway, 5-30 conventional might be an option, or 5-30 full synthetic solves the quandary - cold start protection, or freeway protection.
Keep in mind that viscoscity degradation takes place over time, so that is another reason for 3,000 mile oil changes - to keep the oil within spec. Once again, degradation is slower with synthetic oils.
The second issue to consider in conventional vs. synthetic is, how "hard" do you drive? I mean, how much do you load up your engine, how high to you rev? Engine load can be heavy due to a variety of factors - passenger and cargo load, pulling a trailer, lugging the engine instead of downshifting (throttle is pushed down relatively far, but engine revs are low), driving uphill in the mountains, driving extremely high speeds (wind resistance). A turbo is, ipso facto, high load, because it is pushing more horsepower out of a lower displacement. VW in fact requires full synthetic oils on its turbo models.
So it's really a battle of the marketplace:
Synthetic oils sell for more than they are worth, because they are a premium item with a limited marketplace and its purchasers are less price conscious.
Car makers need better CAFE (corporate average fuel economy) figures so they will push any oil that looks good for fuel economy, and hope consumers will opt out of the designated oil later (thus 5-20 oil for Ford, which needs CAFE, and Honda/Acura which thrives on a "green" image). (Meanwhile the oil VW's "really" need is supposed to be 5-40, which Chevron thinks should be full synthetic due to its extreme range; but VW will accept 5-30 in America - VW cares less about fuel economy, and wants cold start protection, with its side benefit of better cold running fuel economy, but wants operating temperature thickness - hence the "40") (Dodge Neon, both 1999 and 2002, say either 5-30 or 10-30 are ok, provided they are "fuel efficient" - the Neon has a hard working engine with relatively high output.) (Corvettes want Mobil 1. Fuel economy is a foregone concern.)
Car manufacturers want the appearance of low maintenance, but Ford isn't willing to press this beyond 5,000 miles. Honda, once again "green," pushes their intervals to 10,000 miles. VW pushes to 10,000 miles, but they consume so much oil between intervals it becomes a defacto oil change (this is not a jibe, I own one and the oil consumption is the truth - a quart every 1,500 miles, or more often on some cars, up to a quart every 1,000 miles).
Oil companies want to sell oil. Duh. But they also don't want premature engine wear blamed on them. Quaker State, now owned by Pennzoil, still has a promotional "250,000 mile" warranty if you will document your oil use, and change at least every 4,000 miles. (So is 4,000 miles the magic number? It is the same number, by the way, for their dino and synthetic lines.)
What will I run in my cars? Since the VW chews through oil, I am switching to dino oil, and will narrow the viscoscity range from 5-30 to 10-30 for some added viscocity range protection. I think the new SL/GF-3 spec is pretty good. Then when I add quarts of oil in between changes I won't moan. I will change every 3,000 miles to make up for the more rapid degradation of conventional motor oil. I will take my chances on bearing protection and cylinder wall scuffing resulting from high speed driving, hoping that millions of miles driven in Europe with conventional oils means VW's 2.0 liter design is sound, even though it rev's 4,000 rpm at 80 mph.
In the Honda, I will run 5-20 to protect the warranty, but change at 3,000 miles to keep the oil in top condition (less chance to degrade). When the warranty expires, I will switch to 10-30 or at least 5-30, and possibly run full synthetic (the Honda only has a 3.5 quart vs. 4.5 quart capacity on the VW, so there is less oil to absorb abuse). If I run full synthetic, I will extend to 5,000 mile intervals on the Honda to save money.
I am running STP oil filters from Autozone, manufactured by Champion and rated highly on the web. For the VW, I use Bosch right before I go in for dealer service, otherwise STP. I don't let the dealer change the oil, since they use Castrol GTX (not bad, but I prefer Mobil Clean Blend, which is more compatible with Mobil 1 if I switch back; also Mobil Clean Blend has the CF light duty diesel rating, it can hold a lot of dirt).
Well, those are my thoughts. Pity on your employer if you read this long post at work!
Dealers still do not know about this.
Krzys
I'm quite sure someone here has an opinion on that subject, and I'd like to hear it. I'd rather run synthetic in it to take better care of it, unless I'd actually be harming it instead.
Most cars don't bite the big one because of oil failure. I've only had three engine failures in 28+ vehicles none oil related. Something else usually creeps up to make the car undrivable before the engine craps out. Trying to make the engine last for 400K on a 250K car is overkill.
Most cars will do 4K miles easily on just about any SL oil--maybe not some Toyotas, don't know about your VW. I do like 10W30. 5W30 will shear down after 3000 miles but I don't know if there's any proof that it's dangerous. Most 5W20 has enough moly to stay in grade-- don't know if I'd feel comfortable taking a Honda to 10W30 after the warranty period is up. Don't spend enough time on the Edmunds 5W20 threads to form an opinion, but most 5W20 UOA's on Bobistheoilguy seem to be holding up remarkably well.
I change my oil at 4K intervals. If I wanted to go to synthetic I'd probably feel safe at stretching things out to the non-severe driving schedule for my car (Elantra 7500 miles). Would probably do this even with a good group III oil, definitely with a group IV.
I use a SuperTech filter same as your STP. I'd have no trouble pushing it to the 7500 mile mark if I used a synthetic.
http://www.auto-rx.com/index.html
TB
Yes, you are correct.
The problem becomes whether or not it makes a difference to you to mix synthetics group 3 (hydro cracked) as in Castrol etc. with (better) group4 synthetics as in Redline, certain Amsoil, Mobil One. Delvac1, etc.
The unknown with SAAB synthetic oil products is unless you know who the vendor is for their oil, you really don't know if it is a (hydro cracked) group 3 or (PAO) group 4. ( you can probably almost count on the fact that it is the hydrocracked synthetic)
On one hand it really doesn't matter. (as long as it meets SL ratings)
But on the other hand, for example, I personally would not mix Mobil One, except in an extreme emergency with hydrocracked synthetic products. Since I do 15k interval oil filter changes, depending on when I added the "mix" I would not do a full 15k oil change if it has been mixed. If I did a 5-7.5k interval I would have NO concerns at all. If I mixed PAO products, (like Mobil One,Delvac1, Redline, Amsoil) again no concern with 15k intervals
I would suggest you post an inquiry in one of the filter discussions, and I'll bet you get good responses.
Thanks for your input. Excellent information in this thread, I've got a lot of reading to do.
Frank
I wound up going to a truck stop to get Mobil One's diesel sister, synthetic Delvac 1, 5W-40. They speak in different numbers at truck stops. When I asked for Delvac 1, he asked how many cases would I like. (1 case= 4,1 gal containers) So I told him the sump only held a gal and an eighth. He almost busted out. I got a case. It sure takes the better part of a 80 dollar bill
Slightly off topic, but I like the new mileage numbers @ 45/49 mpg. The real world range is between 36-52 mpg.
Bottom line he said Castrol was the best stuff out there. Any comments? Thanks!
Jack
However, did you mean that your owner's manual says to use dino. only? I find that very odd. Could you please copy the verbiage related to the recommendation?
I'd be curious why you do or would think so!
Incidently in line with one of my above latest post about synthetic oil in a VW TDI or turbo diesel, there is an VW TSB that in effect says synthetic oil will be used for subsequent dealer oil products in the TDI. (Read: VW was tired of warranty work on turbo diesels blowing up due to the use of high quality conventional oil.)
http://www.angelfire.com/co3/journal/AmsMyths.html
Page 10-5 from the G35 Sedan owner's manual.
Thanks for that link, that was the kind of thing I was looking for. Although, they don't specificaly mention silicon seals.
I have an I30 and my Infiniti dealer (a very good dealer experience for over five years now) put Mobil 1 in my car (I provided it, of course). If Infiniti recommends mineral based oils, my dealer doesn't subscribe to it. I've talked to several guys at my dealer and they all thought my switch to Mobil 1 was a good move.
bigorange30 "Oil Filters, whose is best, and Why?" Mar 13, 2003 12:06pm
Are the seals different in the G35 than in every other Infiniti? I hope not since I may make the G my next car.
UNIT 2000 MAZDA 626 LX-V6
MI/HR ON OIL 10,000
MI/HR ON UNIT 60,000
SAMPLE DATE 4/6/2003
FIRST NUMBER IS MY OIL AND SECOND NUMBER IS UNIVERSAL AVERAGE
ALUMINUM 7 4
CHROMIUM 2 1
IRON 33 12
COPPER 7 6
LEAD 23 5
TIN 0 13
MOLYBDENUM 75 0
NICKEL 1 0
MANGANESE 1 1
SILVER 0 0
TITANIUM 0 0
POTASSIUM 2 0
BORON 108 38
SILICON 11 9
SODIUM 9 6
CALCIUM 2951 1304
MAGNESIUM 73 481
PHOSPHORUS 801 747
ZINC 963 880
BARIUM 0 1
SUS VISCOSITY @ 210 ºF 64 55-62
FLASHPOINT IN ºF 415 >365
FUEL % <0.5 <2.0
WATER % 0 <0.05
ANTIFREEZE % 0 0
INSOLUBLES % 0.04 <0.6
LAB COMMENT:Nothing too unusual showed up here. This oil was run quite a bit longer that what we
normally see and this is the reason for most of the high wear. The universal averages column shows typical wear from this type of engine after 4,000-5,000 miles on the oil. Lead at 23 ppm shows mildly high bearing wear, though everything else looks okay. The TBN was 3.5 which is low, but not a problem. 2.0 or less is considered a problem. The oil started at 10-11. No fuel or anti-freeze was present. Suggest going 11,000 next oil and resample at that point to monitor.
Ok, my interpretation, excellent results. However, remember that analysis is trend analysis so one sample is extremely hard to interpret. This oil went through the winter so the iron content could be higher due to this. Lead, well, it could be normal for this engine, we just don't know based on one sample. You apparently did not change the filter during the 10,000 but that probably would not make much diff. So, climate, driving conditions, what oil it is, short trips in winter.
This really is a pretty good report, however, I would stay with 10,000 and see what the report looks like after summer driving. If good you have this engine and oil nailed down for the future.
Sure, why not change it every 500 and see just about no wear. the issue is not wear or ppm it is how much wear/mile as wear must occur, it cannot be prevented with todays technology. There is no point to getting 1 ppm in 500 miles or 10 ppm in 5000. The same amount of wear has occurred it just looks better at 500 miles. Now, if you could get .5 ppm in 500 miles by changin oil or conditions then an improvement. There is no proof that more wear occurs in an engine with 20 ppm of iron as opposed to 10 ppm of iron. The particles themself are too small to cause additional wear.
"...the issue is not wear or ppm it is how much wear/mile as wear must occur..."
Better look at the foul you're committing against fundamental logic here, armtdm.
Jack
"It is reasonable to consider the possibility that the rate of wear rises as the miles of use of the oil increases."
yes, but if the wear rate is the same the oil is doing its job. The key is to determine when the oil has used up its' aditive package and the wear rate is about to increase. To play that safe change every 3000 miles or use oil analysis to peg the point that the oil is no longer good and go with that.
As to the Amsoil Series 3000, yes would do better and cold climates mean that there is usually more fuel in the oil due to short trips where the oil does not heat up and burn the fuel off *created by idling a lot and short trips) and condensation is also possible and can result in slightly elevated iron numbers in the analysis.
In fact there is one oil that, based upon analysis, lasts forever the company just has you replenish the additives which they sell separately from the oil.. I forget the name off the top.
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;- f=3;t=000468