I prefer Mobil 1 5-30, but my new Honda requires 5-20 (and apparently it voids the warranty if you use 5-30 instead). What 5-20 do you recommend? I have been using Motorcraft, which is labelled as a semi-synthetic blend, since the other available oils are just "regular" oil. Also, the Ford oil satisfies a unique spec Ford publishes as a requirement for 5-20 oil used in its cars - Ford apparently couldn't get the API etc. people to accept their spec for SL oil in general, so they overlaid their spec on the 5-20 oil instead. Certain critical test cycles have to be run twice as long as the corresponding SL cycle for oil to satisfy the Ford spec.
By the way, I heard that Motorcraft is made by Pennzoil, which, oddly enough, doesn't sell it's own semi-synthetic (although Pennzoil's customer service rep told me both Pennzoil and their cousin Quaker State do satisfy the demanding Ford spec, and Castrol told me the same thing).
Honda has a private label 5-20 oil, but it doesn't say anything about semi-synthetic or the Ford spec (no surprise, they agreed on 5-20 oil but apparently didn't completely agree on going beyond the SL rating), so although it is made by Exxon-Mobil, i.e., the friendly people who brough us Mobil 1, I presently prefer the possibly better engineered Ford oil. Anyone out there have any additional information on the various flavors of 5-20 oil - Ford spec (published), Honda spec (is there one?), SL, semi-synthetic.
Finally, according to Mobil 1, they are coming out with a 0-20 full synthetic that will satisfy the Honda spec (whatever that is; Mobil-Exxon makes the private label Honda oil) but I didn't ask them about the Ford spec; ,maybe it will, since Mobil 1 is a super premium oil and traditionally has satisfied all the "micro-specs" like ACEA wear tests for Mercedes Benz, Japanese valve train wear, etc.
I am debating whether to continue to use Motorcraft semi-synthetic 5-20 in the Honda during the warranty period, with 3000 mile oil changes and STP oil filters, to switch to Castrol GTX (always a good brand, in my opinion better than Pennzoil, or to wait and switch to Mobil 1 0-20 when it comes out and extend to 5,000 miles (less time in the shop). I don't like to go beyond 5,000 miles due to additive breakdown concerns and filter concerns; I buy a premium oil for extra protection, not extended drain intervals.
BTW, for those of you who think oil lasts forever, I rooted around on the web and found one oil company press data sheet that indicated Ford wanted their own WS spec for 5-20 oil because the prior 5-30 SF oil degraded rapidly enough that it lost its fuel saving abilities by the time EPA broke in the engines on their test beds; Ford wanted an oil that would still have the fuel saving capability after a couple of thousand miles. So the oil change companies haven't been lying to us all these years, oil can degrade in important qualities relatively fast. As a person who drives fast across the desert (with carefully inflated tires!) I don't want to micro gall the cylinders on my car....
"additive breakdown concerns and filter concerns" after 5K miles? What is that based on? A good filter will last much longer than that and analysis will show that the additives in synthetics aren't even close to breaking down in a synthetic at 5k in 99% of engines out there.
The viscosity of M1 5w30 is very low in the 30w range, almost a 20w. I have been using it in my 01 LX 4cyl Accord for 89K miles. My Accord was the first year Honda recommended 5w20. In warmer months, I've been known to use 10w30 M1 also.
I believe Motorcraft oil is made by Conoco.
Honda oil is made by Mobil I believe.
Pennzoil and GTX are both good dino oils with moly added when the SL grade started shipping.
Don't be confused by all the "blends" and "synths" on retail shelves. They are mainly group 2 and group 3 dino hydrocracked products. Good oil, but over priced. Mobil 1 is the only PAO based synth readily available on retail shelves.
Also the Motorcraft semi-synth falls into the group 2-3 category. It's no better IMO than Chevron Supreme, Pennzoil,or GTX, all of which use hydrocracked base oil. For 3-4K mile changes, these are all good, but they are not PAO or ester based full synthetic products.
Choose your preferred product and understand it's limitations.
With all the pontification and sermonizing going on these days about 5W20 oil, it's refreshing to see a rational response about it.
The only 2 points that I'd add, is that various oil analyises reported (mine included) show this oil is holding up fairly well when used under 5K miles. Probably the only substantive issue one has to decide is whether or not to use it during the warranty period. And that is so personal, you really have to respect the opinon of the vehilce owner.
89K on M1 5W30, huh? That's the best example I've seen so far that something other than 5W20 at least does no harm. Now you've got me thinking.
not be suited to 1 year oil changes. I posted this in the Engine oil topic:
this is from Bob's board:
This an analysis I had done on my Bud's '01 Monte Carlo. (3.8L) The car is driven like "Aunt Minnie". Almost all short trips of less than 5 miles. He changes the oil every 6 months regardless of the miles.
For what it is worth, both Valvoline and Castrol print statements on their SL grade 5W-20 oil (cases/bottles), that they are intended for use in Ford and Honda products that call for that weight of oil. Castrol further warns to use their product ONLY in vehicles designated for that grade and weight of oil. Now there's a little scare for you. It implies something...
So it seems like if he is forced to change oil every 2k or less miles that economically it might be better to switch to conventional oil and cheaper filter for the conditions and the engine he finds himself employing.
The synthetic oil is still superior but the engine does not function well under the conditions he finds himself running.
However, he might see a difference when he gets the fuel out of the oil. There could also be some other problem in the engine causing this high wear.
If he has eliminated those posibilities, then I would also switch to dino but I don't know if he's going to be able to let a dino go 3k in that engine.
that Schaeffer's has an excellent brew. But to have to order $250 of the product in order to average $2.66/quart is more than I'm willing to do.
Is that like 10 cases? I don't have garage space for that. Wish there was a distributor in my home town. I believe Little Rock is the nearest to my town.
What is the cost per quart for say like buying 6/12 quarts at a time? (Mobil One comes in 6 ea qt containers in a "case") Or what is the shipping charge for any and all quantities under 250. min?
If I have read your post correctly at 2.66 per qt with a 250 min for free shipping that is like app 100 qts or 25 gals. ( actually 93.98 qts or 23.495 gals)
Some other poster on another thread gave the distinct inpression it was 2.66 shipped to his door. Since we were doing a 7 qt comparison I took him at this word that he got 7 qt @ 2.66 for app 18.62. Shipped to his door.
(a gal of water is app 8#s so x 24=192. The last time I priced app 100#s to ship it was like 84 dollars (UPS))
I went to the web site www.schaefferoil.com and got the following: Schaeffer's blend can be had for 4.50 per qt. MIN of 12 quarts not including UPS shipping.
100 qts of Mobil One or Schaffers for that matter would last me in excess of 214,000 miles. My guess is I would do that mileage (one car) in 10 years plus. For a normal 12k-15k a year that is like 14-17 years. I don't think I even keep two oil changes of oil on the shelf. (14 qts or 3.5 gal, let alone 24 gals)
Another unplanned thing that happened to me was, I needed motor oil when I took on gas in Taos, New Mexico. I went over to the local auto parts place and looked for Mobil One 5W-30 and it went immediately into the Vette's engine. Deal Done. The brand is available almost ANYWHERE.
the guy doesn't drive that long on a typical trip. It's killing the oil with fuel dilution and moisture. He might get a better analysis with a schedule of highway trips for ho-ho's, but he's not likely to do it. Short trips like this are killers.
I would agree. Also, some engines run inherently dirtier or cleaner than others. All in all from your information, he has taken a dirty running engine and given it the most severe duty. Of course this is assuming that he is not trending toward a bigger automotive repair.
I currently have a TLC that is run fairly similar to what you describe. It is at 10k on the Mobil One oil change interval. It also is heading toward the 100k (7 oil changes) mark with NO concerns. It has not even had unscheduled repairs or maintenance and is parked outside 24/7 to boot. It customarily needs about 1/4 qt at the 14k mark. I still love this car even though it is going on 10 years old. My baby girl will probably take this to college with her in the fall! I got to telll you that she is the LAST person I want to have car trouble on the road, far from home!!:(
If the 15k mark does not roll around before she leaves, I might be tempted to change the oil before! Just so she doesn't have to take it to a strange place to get service.
Over the last 5 cars, (which now accounts for over 650 miles with no oil related repairs)I have always made it a habit to carefully break in the new car AND change oil @ 1-2k miles when new. After that, I have gone pretty much to the full 15k inteval on all of them. I would guess that the OEM has determined that no "new car" 500 mile to 2k mile oil change is in order, but this is one habit I still do. While the tolerances have probably gotten tighter and the materials better, it seems to me the assembly of a motor hasn't changed much.(having done this myself and watched new engine assembly and assembly lines and custom tuning). I am not aware of the lubrications used in assembly having to meet the SJ/SL standards. They ususually are compatible with motor oil however. The other thing that hasn't changed much is the motors' parts which are machined to exacting standards, STILL have to get used to or form a relationship in the actual engine it has to do the work. I have even gone out with my Vette tuner to do EXACTLY that! (650 hp under the hood on the street is a very interesting feeling!I guess he brought me along for ballast) Makes my 385 hp feel like a VW Beetle!
Given that Schaeffer's costs more than Mobil One, (4.5 plus shipping VS 4.00 to go to 11-12k)(Also we are comparing a 25% synthetic group 2 vs a "full synthetic"). I would stick with the Mobil One.
An interesting but academic test would be a homebrew blend: Mobil One 1 qt/Mobil conventional 4qt (to equal 25% PAO), cost 1.75 qt to see how it stacks up against Schaeffer's blend @ 4.50 a qt.
There are ways to get down the costs of both products I am sure, (I would hazard a guess that both products can be had in 30 gal and 55 gal containers ) but the premise is: off the shelf, wide availability, convenience etc.
I don't have a fraction of the knowledge some of you people out here have regarding synthetic oil. It intrigues me enough to consider switching as I perceive that it may be better for the engine, running cleaner through etc. I have a 98 Infiniti with 95,000 miles, all on dino oil. Would love for the car to last to 200K plus miles, great car! Also have a 96 JGC with 85,000 miles...not as great a car as my Infiniti, but it's been behaving lately and would love for that car to run a long time too.
Is there documented proof synthetics are better? Have I gone too long on the regular stuff for it to make a difference at this point? I'm considering buying the Mobil One and taking it to my dealer and getting a credit back for the oil they're not using.
I am assuming you have been giving your vehicles good maintenance. I think that without a doubt if you continue on your path, you will make it to 200k and beyond, with no oil related failures.
Oil analysis is about as documented as you can get I would think!?
I would give some thought about why you wanted to switch. For example, if you have run close to 100k you have given your engine amble time and conditions to build up sludge. Synthetic oil will not remove sludge. Also, you will not erase the wear already done with conventional oils, but if you switch you will reduce the wear, but using your 200k target, you would reduce only the 100k portion and not the whole 200k portion.
Cost can sometimes be part of the equation and if you don't want to extend the intervals it may actually be more costly to run synthetic oil. A good example would be you are already changing your conventional oil at say 3k and when you switch to synthetic you will still switch at 3k. While you are getting a superior oil, you are increasing the cost say 4x. So you are leaving a large chunk of change at the table, or to be more precise, letting it go down the drain far too early.
I have my vehicles serviced every 5K miles. The Infiniti runs about 18K+/year and the JGC about 15K/year. They are maintained quite well. I have read about intervals, etc. I have always been a believer in changing the oil between 3-5K. With the miles I run up a year I feel the 5K is fine. Could I go 10K or 12K with synthetic and actually be better off becausing I'm using synthetic?
It is obviously more, based on your 4X cost factor, to use the synthetic but the benefit is a sludge free (from the point of using synthetic forward) engine? If you double the interval, then the cost would be twice as much as dino? Am I understanding it correctly?
To my way of thinking yes! If there is any doubt that 10-12k or even 15k intervals are too long there are a number of options, such as build up slowly to it, do oil analysis@ app 20 per analysis. etc.
I personally do 15k intervals with my current 4 vehicles (three are landcruisers, one a vette.)
In your case of 5k intervals with conventional vs 15k intervals with synthetic, parts would be like 11 vs 32 (7qt@ 1 and 4 dollar filter vs 7qt@4=28+4=32) So over the course of 15k miles synthetic actually costs less and you have gotten under your hood 2 less times. If you let the dealer do the oil changes, it is actually 90 dollars (30 per). If you bring the synthetic oil and a filter they usually will charge like 18 dollars labor (plus 32 would cost 50.)
Can I call your attention to the TBN (bottom numbers on the graph illustration) at zero and at 6k miles. 15.5/6.5. Doing the ratios should let anyone PROJECT when the folks in the article will probably need to change the oil. The math would indicate miles and %'s. Wouldn't you agree? So using zero useful life left as the target (you can also use say 5,10,15%, buffer), the question is: what is the % percentage @ 6k and what is the number of miles @zero useful life?
So given the numbers and projects the operative question is: how much of a buffer are you comfortable with, given the TBN is essentially used up at 2? So for me that is why I use a 15k interval with buffer, so I change between 13-14k.
So this brings up the question of: do the conventional oil users really know what their buffer is or do they just take 3k intervals on blind faith? Given the fact that upwards of 98% of folks DO NOT test conventional oil, I think you know the answer to that one!?
ruking, I didn't read the link you posted but are you assuming that the TBN is decreasing linearly? I don't think a single oil analysis can indicate the rate at which TBN drops. I suppose if one compared several analyses with the same engine (e.g. 3.5L Nissan 6-cylinder), same oil, different intervals - you MIGHT be able to determine the way in which the TBN is decreasing.
Also, I am not at all convinced that an engine 'sludges up' simply because it's given conventional oil. Perhaps if the oil is used too long or the vehicle sees extreme duty or something like that. But I don't think it's a given that conventional oil causes engines to sludge up - at least not to any harmful degree.
reading the link he posted would be essential to responding to it. He was not basing it on one analysis at all but 6 of them within the same oil charge and looking at the trend. It really is worth reading.
I am assuming nothing, but reading the TBN number at zero miles (15.5) and reading the TBN number at 6000 miles (6.0)Whether it is linear or not, you can graph it and tell us if it is or it isnt. They also took oil samples at 1000 mile intervals with corresponding reported findings. So in that sense 6 oil samples were taken. So how would you characterize and or explain the decreasing numbers? One way to really tell if the engine is sludged is to take it apart. I merely indicated that with 100k miles, if it did sludge it would have and if it did the synthetic would not clean it out. Let me put it this way, the majority of sludged engines that I personally have seen is with conventional oil. Sludge as you know can be pretty well removed using the Bosch hot solvent system flush. The only thing is that it is fairly costly. Synthetic oil is FAR less susceptible to sludging. I have seen all of mine sans the Vette and not only did they look clean as a whistle to me, but the dealers' mechanics think so also . Trust me, telling me that runs counter to their self interest, in that if it were not they would love to hit me for maintenance if the specifications are not to factory specifications. The most important component is the analysis about 100k in conventional vs 100k synthetic component wear patterns.
Also my other point is that conventional folks do not do oil analysis such as the article described for the synthetic. This experiment is easily replica table with CONVENTIONAL oil. It would be great to take samples of conventional oil at 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15k. as is the intention of the articles experimenters. It would be an interesting eye opener to run these tests side by side with a brand name recognized conventional brew.
I have primarily gotten the 5qt jugs at WalMart. It is a hit or miss type of event. All in all it seems like a twice a year catch as catch can event although if you talk to someone in the know at your local WalMart, they can probably be more specific. I know that there is at least a dollar savings having one container instead of 5. Not to mention less to throw away or recycle. the last jugs I bought cost like 17.88 each.
I have priced Redline and it is around8.30 a qt, over 6 qts @ 7.95 not including shipping.
so let's say I find 5qtr jugs of mobil1..I would buy 2 of them for two oil changes. Which in my case would be aprox. 6 months apart(I run 10000 miles oil change interval). This brings me to ask what is the shelf life of the synthetic oil?
There is no official shelf life of oil. However if you check the fine print of conventional and synthetic oil, for its intended use, almost EVERY oil manufacturer will say change your oil at least yearly. EVEN Redline and Amsoil say that.
No, not at all!!! I bearly keep the full quantity for my next oil change on the shelf! But my oil changes are staggered a bit so not all of them becomes due on like March 20th. To my way of thinking 1 qt bottles are 1 -4 dollar bills sitting on the shelf!? In the case of the 5 qt that would be 17.88.
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The only reason I'm doing that is that it is hard to find a 5qtr jug of Mobil 1(and it saves money to buy it in 5qtr jug)...Actually yesterday I called 5 Walmarts in my area (I live in DC) and none of them had any. They said that 5qtr jugs come only from time to time as a promotion :-(
Comments
By the way, I heard that Motorcraft is made by Pennzoil, which, oddly enough, doesn't sell it's own semi-synthetic (although Pennzoil's customer service rep told me both Pennzoil and their cousin Quaker State do satisfy the demanding Ford spec, and Castrol told me the same thing).
Honda has a private label 5-20 oil, but it doesn't say anything about semi-synthetic or the Ford spec (no surprise, they agreed on 5-20 oil but apparently didn't completely agree on going beyond the SL rating), so although it is made by Exxon-Mobil, i.e., the friendly people who brough us Mobil 1, I presently prefer the possibly better engineered Ford oil. Anyone out there have any additional information on the various flavors of 5-20 oil - Ford spec (published), Honda spec (is there one?), SL, semi-synthetic.
Finally, according to Mobil 1, they are coming out with a 0-20 full synthetic that will satisfy the Honda spec (whatever that is; Mobil-Exxon makes the private label Honda oil) but I didn't ask them about the Ford spec; ,maybe it will, since Mobil 1 is a super premium oil and traditionally has satisfied all the "micro-specs" like ACEA wear tests for Mercedes Benz, Japanese valve train wear, etc.
I am debating whether to continue to use Motorcraft semi-synthetic 5-20 in the Honda during the warranty period, with 3000 mile oil changes and STP oil filters, to switch to Castrol GTX (always a good brand, in my opinion better than Pennzoil, or to wait and switch to Mobil 1 0-20 when it comes out and extend to 5,000 miles (less time in the shop). I don't like to go beyond 5,000 miles due to additive breakdown concerns and filter concerns; I buy a premium oil for extra protection, not extended drain intervals.
BTW, for those of you who think oil lasts forever, I rooted around on the web and found one oil company press data sheet that indicated Ford wanted their own WS spec for 5-20 oil because the prior 5-30 SF oil degraded rapidly enough that it lost its fuel saving abilities by the time EPA broke in the engines on their test beds; Ford wanted an oil that would still have the fuel saving capability after a couple of thousand miles. So the oil change companies haven't been lying to us all these years, oil can degrade in important qualities relatively fast. As a person who drives fast across the desert (with carefully inflated tires!) I don't want to micro gall the cylinders on my car....
I believe Motorcraft oil is made by Conoco.
Honda oil is made by Mobil I believe.
Pennzoil and GTX are both good dino oils with moly added when the SL grade started shipping.
Don't be confused by all the "blends" and "synths"
on retail shelves. They are mainly group 2 and group 3 dino hydrocracked products. Good oil, but over priced. Mobil 1 is the only PAO based synth readily available on retail shelves.
Also the Motorcraft semi-synth falls into the group 2-3 category. It's no better IMO than Chevron Supreme, Pennzoil,or GTX, all of which use hydrocracked base oil. For 3-4K mile changes, these are all good, but they are not PAO or ester based full synthetic products.
Choose your preferred product and understand it's limitations.
The only 2 points that I'd add, is that various oil analyises reported (mine included) show this oil is holding up fairly well when used under 5K miles. Probably the only substantive issue one has to decide is whether or not to use it during the warranty period. And that is so personal, you really have to respect the opinon of the vehilce owner.
89K on M1 5W30, huh? That's the best example I've seen so far that something other than 5W20 at least does no harm. Now you've got me thinking.
this is from Bob's board:
This an analysis I had done on my Bud's '01 Monte Carlo. (3.8L) The car is driven like "Aunt Minnie". Almost all short trips of less than 5 miles. He changes the oil every 6 months regardless of the miles.
Schaeffer labs did the report
Miles on Car 7220
Miles on oil 1503
Oil Filter: A/C DELCO Ultra Guard gold
copper.......90
iron.........16
chromium......1
aluminum......3
lead..........4
moly.........79
phospherous.943
zinc........945
magnesium...372
calcium....2770
anti-freez ..0%
Fuel Dilution..positive
H2o...........0.2%
silicon......14
viscosity cst...8.63
sae/iso......20w
sulfur.......16
oxidation.....0
nitration....19
Comments were viscosity reduction due to fuel dilution
Oil s/b changed
The synthetic oil is still superior but the engine does not function well under the conditions he finds himself running.
If he has eliminated those posibilities, then I would also switch to dino but I don't know if he's going to be able to let a dino go 3k in that engine.
The lab said to extend the drain interval to 11300. Synthetic is good, but I don't think it'll do 5 times that.
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;- f=3;t=000377
ITAP,
Jack
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;- f=3;t=000197
http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;- f=3;t=000320
Is that like 10 cases? I don't have garage space for that. Wish there was a distributor in my home town. I believe Little Rock is the nearest to my town.
If I have read your post correctly at 2.66 per qt with a 250 min for free shipping that is like app 100 qts or 25 gals. ( actually 93.98 qts or 23.495 gals)
Some other poster on another thread gave the distinct inpression it was 2.66 shipped to his door. Since we were doing a 7 qt comparison I took him at this word that he got 7 qt @ 2.66 for app 18.62. Shipped to his door.
(a gal of water is app 8#s so x 24=192. The last time I priced app 100#s to ship it was like 84 dollars (UPS))
Another unplanned thing that happened to me was, I needed motor oil when I took on gas in Taos, New Mexico. I went over to the local auto parts place and looked for Mobil One 5W-30 and it went immediately into the Vette's engine. Deal Done. The brand is available almost ANYWHERE.
I currently have a TLC that is run fairly similar to what you describe. It is at 10k on the Mobil One oil change interval. It also is heading toward the 100k (7 oil changes) mark with NO concerns. It has not even had unscheduled repairs or maintenance and is parked outside 24/7 to boot. It customarily needs about 1/4 qt at the 14k mark. I still love this car even though it is going on 10 years old. My baby girl will probably take this to college with her in the fall!
If the 15k mark does not roll around before she leaves, I might be tempted to change the oil before!
Over the last 5 cars, (which now accounts for over 650 miles with no oil related repairs)I have always made it a habit to carefully break in the new car AND change oil @ 1-2k miles when new. After that, I have gone pretty much to the full 15k inteval on all of them. I would guess that the OEM has determined that no "new car" 500 mile to 2k mile oil change is in order, but this is one habit I still do. While the tolerances have probably gotten tighter and the materials better, it seems to me the assembly of a motor hasn't changed much.(having done this myself and watched new engine assembly and assembly lines and custom tuning). I am not aware of the lubrications used in assembly having to meet the SJ/SL standards. They ususually are compatible with motor oil however. The other thing that hasn't changed much is the motors' parts which are machined to exacting standards, STILL have to get used to or form a relationship in the actual engine it has to do the work. I have even gone out with my Vette tuner to do EXACTLY that! (650 hp under the hood on the street is a very interesting feeling!I guess he brought me along for ballast) Makes my 385 hp feel like a VW Beetle!
Given that Schaeffer's costs more than Mobil One, (4.5 plus shipping VS 4.00 to go to 11-12k)(Also we are comparing a 25% synthetic group 2 vs a "full synthetic"). I would stick with the Mobil One.
An interesting but academic test would be a homebrew blend: Mobil One 1 qt/Mobil conventional 4qt (to equal 25% PAO), cost 1.75 qt to see how it stacks up against Schaeffer's blend @ 4.50 a qt.
There are ways to get down the costs of both products I am sure, (I would hazard a guess that both products can be had in 30 gal and 55 gal containers
Is there documented proof synthetics are better? Have I gone too long on the regular stuff for it to make a difference at this point? I'm considering buying the Mobil One and taking it to my dealer and getting a credit back for the oil they're not using.
Any guidance would be very much appreciated!
I am assuming you have been giving your vehicles good maintenance. I think that without a doubt if you continue on your path, you will make it to 200k and beyond, with no oil related failures.
Oil analysis is about as documented as you can get I would think!?
I would give some thought about why you wanted to switch. For example, if you have run close to 100k you have given your engine amble time and conditions to build up sludge. Synthetic oil will not remove sludge. Also, you will not erase the wear already done with conventional oils, but if you switch you will reduce the wear, but using your 200k target, you would reduce only the 100k portion and not the whole 200k portion.
Cost can sometimes be part of the equation and if you don't want to extend the intervals it may actually be more costly to run synthetic oil. A good example would be you are already changing your conventional oil at say 3k and when you switch to synthetic you will still switch at 3k. While you are getting a superior oil, you are increasing the cost say 4x. So you are leaving a large chunk of change at the table, or to be more precise, letting it go down the drain far too early.
It is obviously more, based on your 4X cost factor, to use the synthetic but the benefit is a sludge free (from the point of using synthetic forward) engine? If you double the interval, then the cost would be twice as much as dino? Am I understanding it correctly?
Thanks for the info!
I personally do 15k intervals with my current 4 vehicles (three are landcruisers, one a vette.)
In your case of 5k intervals with conventional vs 15k intervals with synthetic, parts would be like 11 vs 32 (7qt@ 1 and 4 dollar filter vs 7qt@4=28+4=32) So over the course of 15k miles synthetic actually costs less and you have gotten under your hood 2 less times. If you let the dealer do the oil changes, it is actually 90 dollars (30 per). If you bring the synthetic oil and a filter they usually will charge like 18 dollars labor (plus 32 would cost 50.)
This might be an interesting article:
http://neptune.spacebears.com/cars/stories/oil-life.html
Can I call your attention to the TBN (bottom numbers on the graph illustration) at zero and at 6k miles. 15.5/6.5. Doing the ratios should let anyone PROJECT when the folks in the article will probably need to change the oil. The math would indicate miles and %'s. Wouldn't you agree? So using zero useful life left as the target (you can also use say 5,10,15%, buffer), the question is: what is the % percentage @ 6k and what is the number of miles @zero useful life?
So given the numbers and projects the operative question is: how much of a buffer are you comfortable with, given the TBN is essentially used up at 2? So for me that is why I use a 15k interval with buffer, so I change between 13-14k.
So this brings up the question of: do the conventional oil users really know what their buffer is or do they just take 3k intervals on blind faith? Given the fact that upwards of 98% of folks DO NOT test conventional oil, I think you know the answer to that one!?
Also, I am not at all convinced that an engine 'sludges up' simply because it's given conventional oil. Perhaps if the oil is used too long or the vehicle sees extreme duty or something like that. But I don't think it's a given that conventional oil causes engines to sludge up - at least not to any harmful degree.
One way to really tell if the engine is sludged is to take it apart. I merely indicated that with 100k miles, if it did sludge it would have and if it did the synthetic would not clean it out. Let me put it this way, the majority of sludged engines that I personally have seen is with conventional oil. Sludge as you know can be pretty well removed using the Bosch hot solvent system flush. The only thing is that it is fairly costly. Synthetic oil is FAR less susceptible to sludging. I have seen all of mine sans the Vette and not only did they look clean as a whistle to me, but the dealers' mechanics think so also . Trust me, telling me that runs counter to their self interest, in that if it were not they would love to hit me for maintenance if the specifications are not to factory specifications. The most important component is the analysis about 100k in conventional vs 100k synthetic component wear patterns.
Also my other point is that conventional folks do not do oil analysis such as the article described for the synthetic. This experiment is easily replica table with CONVENTIONAL oil. It would be great to take samples of conventional oil at 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15k. as is the intention of the articles experimenters. It would be an interesting eye opener to run these tests side by side with a brand name recognized conventional brew.
I have priced Redline and it is around8.30 a qt, over 6 qts @ 7.95 not including shipping.
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Hope to see you there!
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2015 Kia Soul, 2021 Subaru Forester (kirstie_h), 2024 GMC Sierra 1500 (mr. kirstie_h)
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