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I would not use an engine flush made by any manufacturer. My idea of flushing my engine is a short-interval oil & filter change ... nothing more.
Those MB recommendations are weird ... VERY WEIRD. I liked adc100's suggestions, though. >:^)
--- Bror Jace
brorjace: I was going to switch to Redline on my new Sentra (4K) but I wimped out since it was less then the 10K recommended. Was it you who gave the link on Manchester Motor Sports for the Redline and if so is this still a good place??
Thanks,
Al
Do you think it's a bad idea to mix brands? I've got about 4 qts of Castrol GTX and a couple quarts of Valvoline.
Bluedevils, it USED to be (10-20+ years ago) conventional wisdom not to switch brands (whether it really mattered or not, who knows?) but with the newer formulas all conforming to increasingly stricter standards, I'm guessing the oils are becoming more and more similar.
As for mixing synthetic and regular oils, I've done it all the time in my Civic which now has over 100,000 miles on it ... with no discernable ill effects. My car burns no measurable amount of oil between changes.
--- Bror Jace
Just follow the manual and select a weight in the proper range.
BrorJace - I just replied to your post to me about the Amsoil P.I. Lol!
What baffles me most is that we sometimes take it upon ourselves to second guess the manufacturer to decide what is the best oil to use. I'm going to start picking on people now:
"bidandsell" - What makes you think Honda didn't know what they were doing with their 5W-20 recommendation? What makes you think that what is right for the CAT engine is right for the Honda? Depending on engine size, intended use, or engineer preference, the metals used on inernal parts could have varying specific heats or clearances that require a lower viscosity oil to provide proper lubrication. Honda may just be making the recommendation to increase fuel economy to meet ULEV requirements, but they aren't going to recommend anything that is harmful for the engine. I'm not saying that using 10W30 is going to do any damage, but if Honda took the time to figure out the best oil to use in that engine under given conditions, why would you dispute that? And, on what grounds?
"mrgeorge," you're next. I'll just flat out say it - I don't believe you can feel a difference between 15W50 and 10W30. The difference would be so subtle that a dyno would be required to detect the change. Oh, there's a difference, I'm sure - just nothing that you could detect. It's probably all above the eyebrows.
Hey, when was the last time you heard of a properly maintained modern engine without existing mechanical problems failing because of oil? I'll admit, I'm a Mobil1 user - and I wouldn't have it any other way. But, it seems like a bunch of people here view mineral oil as deadly poison for their engines. That's simply not the case. And, all these weird things like a "din-oil enema????" Where do you guys come up with this?
I won't claim to know everything about engine oil or the all about the metallurgical composition about all different engines, but far more research goes into engine design that anybody here seems to realize. The same holds true for the oils that lubricate them. You wouldn't practice medicine without extensive training and proper licensing because you DON'T HAVE THE KNOWLEDGE. Knowing HOW a heart works doesn't automatically qualify you to fix one or prescribe treatments for a patient. So, why would someone with no knowledge of fluid mechanics, metal structure, parts interactions, viscous effects, shear forces, film strengths, and so on. . . feel qualified to supercede recommendations for the people who built their engine??
My point is, you all are wasting time debating over oil like this. Only I am wasting more time chiding you all for it. Here's simple: Throw in the recommended grade of Mobil1 and a quality filter into your new car. If youre older car is running great with mineral oil, why change? Just keep doing what you're doing. If you don't want to shell out the extra cash for the synthetic, then use the store brand oil of proper grade. In the interest of simplicity, I'm not going to re-hash my additives lecture I gave a few weeks ago.
If you're just curious about things and enjoy this discussion, by all means continue! I don't want to stifle conversation, but argument for the sake of argument is non-productive. At least talk about WHY certain oils are used in different applications. Discuss WHY Honda, Toyota, has varying lubrication requirements for engines of similiar displacement and intended service use. Talk about WHY service schedules differ between manufacturers under the same service conditions (other than government conspiracy and mutual benefits of frequent drain intervals with oil companies - that's hooey). At least we can talk about something intelligently rather than say "Duh, that oil just seems too watery to put in my engine." Back it up with something, will ya!?
I'll wait for your complaints.
And believe it or not, for the most part, I agree with your post. I also have no problem with you taking "a swipe" at posters. That's fair game.
So now comes my portion of either stupidity, pompous declarations, etc:
You indicated that Honda knew what they were doing when the recommended their 5W-20 oil. I'm sure they did. I'm guessing they sacrificed some engine life for better gas milage. There's nothing wrong with that, if the engine life is acceptably long. It also may be a mistake and Honda may come out with an other recommendation down the road because the oil did not pan out. History is full of corporate bungles: The unsinkable Titanic sunk, Three Mile Island blew up, 11 mile per hour wind blew a 100 mil suspension bridge down, Morton Thiokal O-Rings failed because the Corporate Suits were political animals, I could go on. Many vehicles have proven unsatisfactory in the past because of bad engineering or applications. You are far too trusting of manufactures, government, and big business. I don't ascribe to all these conspiracy theories. But I have been a practicing Mechanical Engineer in a large corporation for 32 years. I hold a healthy doubt about some things. If you are younger and early in your career I'd suggest this mode of operation. For me this is one of those doubts. Not sure if I complied with your last paragraph or not.
Later,
Al
The family immigrated from USSR. Never had car before. No money nor job. To be capable to drive to job interviews, bought a very old used car, and somebody suggested them not wasting time and money on service.
A year later, already with decent job(s), they bought a cheap new car - but continued with the "no service" advice. Never changed oil. Engine died at 70k+ several years later.
Then they already had a good job, not the initial position. Junked the car and bought a much better one.
The driving is considered "normal" if it consists mostly of long trips on the flat roads. Short trips (less than 10 miles), stop-and-go traffic, idling, dust, and towing are severe conditions. For transmission severe are also hilly and mountainous terrains. I.e., living in / near big city, as well as such places as California, Washington, or even hilly New England makes driving "severe" automatically.
Though, very few people are towing or driving in stop-and-go traffic all the time.6000 miles are close enough to 5000 miles. Sounds fine, or rather a bit on the safety side.
I don't think that "ultimate protection" is the biggest concern for most drivers, but, rather finding the most economical service schedule that will still ensure long-term, trouble-free operation. A lot of folks prefer to adhere to 6000 mile drain intervals with synthetic oil rather than use mineral oil at 3000 mile drain intervals. The cost/mi is still higher, but some people accept this as the trade off for having to make one less oil service over the 6000 mi driving period. Ideally we would all have Hobbs meters and change the oil based on engine hours (again, with a severe service clause).
The biggest problem faced by the world's crankcases is condensation. Moisture typically accumulates in the evening hours when the temperature drops below the saturation temperature of water. Another large source of H2O in the engine occurs from the by products of hyrdocarbon combustion: HC's + O2 -> H2O + CO2 (I'm leaving the stoichiometry out.) Yeah, there are other reactions going on, too, but they are negligible for this conversation. When you first start a cold engine the fuel/air mixture is controlled by a preprogrammed map in the engine computer. This is termed "open loop" operation since the computer doesn't really care what the conditions of the engine are at this point to control mixture. All the computer knows is that the engine is cold and the O2 sensor is no good until it reaches a certain temp. So, typically this mixture is rich - meaning there is a fuel/air ratio > 14.66. This means there is excess fuel in the exhuast stream (a small amount, but significant if the engine is run cold often).
Now, picture the cylinder and piston when the engine is cold. In order to provide a reasonable fit between the piston rings and the cylinder wall at operating temperature so as to not produce binding or excess friction drag, the pistons are manufactured so that the ring diameter is slightly smaller than the cylinder diameter. As the engine warms up, the clearance between the cylinder wall and the piston ring decreases. When the engine is cold, a greater amount of gasses blow by the piston rings and into the crankcase. And, in these gasses is some unburned fuel and water vapor.
A little more chemistry: What happens when you mix CO2 and H20? Ever drink soda? Well, you get HCO3 - carbonic acid. Over time this can be corrosive to internal engine parts. That is why engine oils contain additive packages with buffers specifically designed to neutralize acid formation. IMPORTANT: Most often it is the additives that expire first in a motor oil.
Again, under ideal situations, we would always drive our cars long enough to warm up the engine and boil off the excess gasoline and water in the crankcase. When that isn't convenient (you live a mile from work), these contaminants accumulate and "consume" the additives in the oil.
Lots of good news, though. Engine management (fuel delivery, combustion efficiency) and manufacturing processes have drastically reduced the blow-by gasses at startup. Also, engines are designed to heat up more quickly and provide an environment suitable to expell the contaminants sooner than older engines. So, this is much less a problem in modern FI engines than in older carb'd engines - though it is still a notable factor.
Lightly touching on the base stock: Higher speeds generally denoted higher engine oil temperatures. Often - especially in turbos (and mostly on shut down) - oil coking becomes a problem and can break down the base stock sooner. Synthetics are more resistant to high temperature breakdown, and probably aren't subject to as rigorous a severe service schedule requirement as are vehicles using mineral oil for high-speed highway use. Otherwise, within the time span of additive life, mineral vs. synthetic stock will still perform as intented. (Geez, there are a lot of angles I could take here. . . ) Moving on.
Having prefaced with that: Knowing that most of us don't have hour gauges, we have to pick a service schedule based on the only other thing we can measure accurately - mileage. And, from that, we break it down it to "servere" and "normal." You can never go wrong with the severe service schedule, but you hit the economic wall. Why pay more than you should, right?
I've seen studies a few years back that compared engine wear with different oils and different service schedules for NYC cabs. That's not a good real world comparison. The engines are always warmed up, and there's few startup/shutdown cycles in a day - if any. Subsequently, this study concluded there was little if any difference between different brands of mineral oils and that changing oil at 3000 mi was a waste of money - which, I'm inclined to beleive under those service conditions. Again, with such constant use, they are probably on an hourly change schedule.
Ok, back on track. Decide if you are truly a severe service user, or a normal service user. If you get that puppy warmed up and drive it at least 10 miles per trip (trip=cold-hot-cold cycle), then consider yourself normal service. Is there a mileage/month recommendation, or just a mileage recommendation? Often they'll say something like 5,000mi or 5 months - whichever comes first - like your warranty. If you use a quality synthetic like Mobil1, and you are a legitimate normal service user, then don't think twice about 10,000 mi drain intervals. If it really bothers you, and you don't mind paying more out-of-pocket per mile, then change it at 6,000. But, my recomendation would be to stick with 10,000 mi with a synthetic. Still, however, that is one of the longest drain intervals I've seen for a production vehicle. Perhaps this is a testament to Honda's ULEV quest and super-efficient engines. You'd probably be just fine using a mineral oil, but most people aren't here to parse the benefits of "dino-juice," but instead expand on the many benefits of synthetics.
Sorry I rambled, but hope this answers any questions you may have had along the way.
Also, (I can never be brief, can I?), because of the purity of synthetic oil, over extended drains of 10,000mi, you may notice (ok, maybe not NOTICE) few deposits within the engine. There's lots more to consider, too, but I don't have the time right now. Until then. . .
I notice you love those Hondas and yet drive a Dodge??? Whats up with that?? (jab-jab). Anyway good technical post. I'll read again later- its too early. One thing on the discussion of the ring clearances, you said " ring diameter is slightly smaller than the cylinder diameter."- ring OD is always larger than the cyl bore. I realize the piston grows faster than the cyl and the rings grow faster than the piston. All of this changes the size of the ring gap. Maybe you were referring to the diametral clearance between the piston OD and ring ID?? Like I said- it's early, I'm slightly comotose yet.
I do agree with your time lines for oil changes, but don't forget about the filter changes. I wouldn't run filters over 5 or 6 K. I know that's conservative, but that's me. As I recall a lot of GM's with those very small filters in their small block V-6's indicated a change every other oil change (15K woohoo to long for me)
Later
Al
I've never driven a Honda as my long term vehicle. For 7 years I drove a 1984 Olds Firenza. I finally unloaded that with 182,000 (110,00 mine) because of a worn crankshaft snout - NOT internal engine wear. The crankshaft timing belt sprocket loosened up over time causing constant shifting and scoring on the crankshaft end. I got a new sprocket and JB Welded that bad boy to the crankshaft. It was a one shot deal - otherwise I'd be shoving a rope down #1 looking for TDC. To avoid further time consuming repairs I decided to trade up. Anyway, the Durango was a good deal that happened to come along, which explains why I'm driving it.
Interestingly enough, I used mineral oil ever since I purchased the Olds. Straight-off-the-shelf Pep Boys 10w-30 or in the summer straight 30. Compression between cylinders was still great in the end, and she never used any oil. A purolator or Autozone Deutch brand filter accompanied each oil change at 4,000 miles. The very last oil change I did was synthetic. Don't ask why, I just did it. No problems with seals or seepage from gaskets. Didn't notice any increase in fuel economy or power over the 7000 on that oil change (not much to begin with). Who's to say about seals if I drove it longer. I'm kind of curious, 'cause I hear so many people mention it, but haven't witnessed any cases of the dread seal leaks in older engines switched to synthetic. The Durango has had synthetic since about the 4th drain (absolute, not just since I've had it).
adc100 - a quick note about filters - which do you use, and what engine application are you using? I read a review by a fellow who cut open a dozen or so name brand filters from OEM, to store brand, to ultra-premium. He made an interesting comment that it appeared as though several had cheap (shoddy) drainback valves that would allow the oil (when the filter mount was inverted or on it's side) to drain back through the gallery into the pan. Depending on your engine design this could cause some minor cavitation in the pump at startup and lead to delayed rise in pressure, thus causing your noise.
The only time I ever hear valvetrain noise on startup is immediately folloing an oil change. I try to pre-fill the filter, but with a side mount, I'm limited at how much I can add. Otherwise, I never hear valve noise, and I've got good pressure in a second or two tops.
What I'm saying, I guess, is that you might try swapping filter brands if you haven't already tried and see if that makes a difference. I remember hearing that Ford's Motorcraft brand was one of the better filters when considering drainback valves and filter media capability (next to the ultra-prem's - 10 bucks - ha!). I'll look up the URL later and post it. Good reading.
Mobil 1 and had startup noise. Switched to Pure One and problem went away. '92 Corsica- Vertical and no problems. I hate horizontal mounts. Unfortunately it's a matter of design convenience and not based on good engineering requirements. I had an '88 Ranger that I used mostly AC's in. The ford man asked me at that time if I didn't realize the AC had no drainback valve in it. I said to myself-so thats why this thing is so noisy on startup. Ford filters had, as ytou indicated good anti-drainback valves. I believe this was one of the problems with this engine. The filter was the large one (FL-1??) Took forever to fill it on every startup. Believe it or not the Truck is still on the road with 140K-amazing.
Whether Amsoil is better than Mobil 1, who knows. All the Amsoil dealers out there will try to convince you that their oil is better (I'd love to see a test by a reputable organization or laboratory to prove this). I would get Mobil 1, simply because its available everywhere and less expensive.
IMHO I would also recommend going to oil changes at intervals of at least 5K miles (or once a year if you drive less than that) and use a quality oil filter (like Purolator PureOne, Amsoil and others, its your personal preference).
As others have said before me, compared to the price of a new car (engine), a little money spent on a good quality synthetic oil and filters seems like a very good investment.
Here's a quote: "Due to its superior synthetic composition and advanced performance additives, AMSOIL 10W-30 performs much longer than do conventional petroleum and other synthetic motor oils. No other major oil manufacturer matches AMSOIL's 25,000-mile or one-year drain interval recommendations."
If this is true I think I'd go for it. Anyone have any comments on this?
I realize that you never specified the engines you were talking about. Perhaps that might make it more clear.
If you really want to go 25K miles between changes you better make sure you do an oil analysis at half this mileage and only if your engine is sound!
Mark
http://www.amsoil.com/products/tso.html
The catch words are "one year". How many people put 35,000 miles per year on their personal car? Of my friends, only one approaches 30,000 miles (60 mile one-way commute), and one couple approaches 25,000 miles.
On the same page Amsoil recommends shorter change intervals for fleets, to do under oil analysis control. Quote: In fleet ...: drain oil at intervals up to three times as long as those recommended by the engine manufacturer if the findings of a used oil analysis program support the extended drain intervals.
The oil filter must be changed at least 2-3 times as often as the oil itself, according to Amsoil.
You can scroll back up and find post #1393. If you want further info-email me.
Bottom line - both oils can go the distance. But for me 25K is too long. Oil analysis is needed. Its silly to go that long. (in my opinion)
Medecamps- appearance is no indication of the superior product. (oil may be cleaner and engine dirtier). Valvoline is also a PAO/Ester oil. I use mobil because of the testing I read in an SAE Technical paper. Can't say the same for other oils. Valvoline may be better, But I can't prove that.
Today, with changing recommendations, that's not so much the case. I'm sure car makers still predominantly use petrol oils because they are cheap, but there's no reason why you couldn't use synthetic on the first fill. It won't adversely affect engine performance or break in. I'm not advocating people to drive their car off the dealer's lot and drain the oil immediately, though. There will be no harm in using the factory fill until the first service. Again, why spend more than you need to?
I am aware that some car makers still use a factory fill with a "break-in" oil. DC may still do that on some engines, though I can't be sure. Without any technical knowledge on that, I stop short of a lengthy commentary. But, should that be the case, then whatever special additive package the manufacturer uses should stay in there for the duration of the break-in period.
Just a little tidbit. Later.
The 5000 mile change is a twin turbo, my 133,000 mile Toyota is a 7,500 change, my 96 Mystique is once a year, comapny car is every 12,000, SUV at 7,500. Numerous oil analysis has shown that about 12,000 is max for me, wear metals etc all fine but the silicon (dirt) begins to build up as no oil filter made (except a bypass) can get particles below 10 microns.
Yea, 25,000 possible but the fine print needs to be read here, AMSOIL says 25,000 or one year with a filter at 6 months or 12,500 if an Amsoil filter. Not many people put on 25,000 miles in a year. So in reality, 12,000-15,000 between changes very realistic which is once a year for most people.
I realize that it said 25k or 1 yr & the filter had to be changed at 12.5k or 6 mos, whichever comes first, I was just amazed that the interval could be that long.
I put about 15k a year on my JGC, so I wouldn't even get close to the 25k in a year. & I agree, adc100, it is silly to go that far between changes without testing the oil.
Polgomaus, I agree that they can say anything they like in print, but according to adc100 they back it up with a warantee.
But thanks, armtdm, for saying that 12k-15k between changes is realistic, 'cause that's perfect for me. I would change the filter after about 7.5k or 6 mos as well, yurakm.
Ok, well thanks again - in about another 2,000 miles I'll drain out the dino-oil for the last time & load it up with the Amsoil!
I realize that many people today have never had a car with a carburetor, but with the choke on during a cold start and warm-up a lot of unburned fuel got to the oil. Remember the chugging and missing on a cold start? The unburned gas depleted additives and caused viscosity breakdown.
Still, before you were mentioning the 15W40 used in the cat engines. Without reviewing your prior posts it looked like you intended to use 15W40 in the Honda! It seems clear now that you were only using that example to demonstrate perceived advantages of more viscous oil. The 5W20 move on Honda's part clearly appears like a move in favor of fuel economy. However, I dare say they would make a recommendation to improve fuel economy at the expense of engine wear. This is suicide from a marketing standpoint, especially from a company that has long prided itself on robust engines. That last statement was speculation and should be left to a different discussion. Pardon me.
The CAT engine was designed for use at angular velocities (rpms if you will) much lower than your Honda is capable of turning. I really wish you would say which engines you are comparing so I could make better educated statemets. But "high idle" for a large diesel engine (Cummins L10) is about 1800 rpm. The PTO load is not extremely taxing on the engine at this speed, either, but the hydraulic pumps require it to generate pressure. At higher RPMs in your gas engine you run the risk (ever be it small) of starving a bearing for oil if you use a higher than recommended viscosity. The 30 weight isn't going to flow as quickly to parts with small clearances, which doesn't become such an issue with slower turning engines. If 10W-30 was good enough for last year's mechanical twin , then it is probably just fine now. The 5W20 requirement must be made, though, to meet fuel economy claims. Also, torque ouput is undoubtedly higher in this CAT engine (whatever it is), thus equating to greater internal stresses at contact points such as crankshaft bearings/journals as well as connecting rods. The 10W40 will offer a higher film strength under those operating conditions.
My biggest beef is not that you choose to fill your Honda with 10W30, but the reasoning that you employ to justify its use. Thicker oil doesn't necessarily equate to less wear. If you spin a bearing at full tilt because of starvation, how's that thicker juice going to help (there's none there)? The thinner fluid would have prevented the situation in the first place. Synthetic oil use provides further protection with greater film strengths over petroleum base stocks, so you can afford to use a thinner oil as per MANUFACTURER'S DIRECTIONS. Again, let me iterate that the 10W30 is just fine, but I'm attacking your reasoning. That's essentially saying that using thicker oil will protect your engine better. If that's the case, why not throw in 75W90 gear oil left over from the last diffy fluid change on the pickup truck?
It's difficult for us to grasp the concept of viscous fluid flow and its properties within an engine and among moving parts. Sure, we can shake the bottle and swirl our finger around in the oil, but what does that tell us? It lets us know only that 20 weight is less viscous than 30 is more fluid than 40. . . and so forth. So, how does that quantitatively define lubrication performance in your engine? Those are things that can really only be tested and verified accurately by people with lots of money to do those tests. I guess oil analysis would reveal a lot, but, what if there is no difference? Then, we make blind assesments of what various oil specifications will do for OUR engine based on tests in other engines. It's a real jungle science game we try to play when comparing results between engines of 1. Different load designs; 2. Drastically different operating speeds; 3. Typical use parameters (city shifting and often variable rpms vs. constant engine speed).
If you can, let me know what kind of CAT engine you are using to make your comparisons. If you don't have a model, how about the equipment it was in. Just more food for thought.
Oh, adc100: here's the URL I promised from the other day on oil filters: http://members.nbci.com/minimopar/oilfilterstudy.html
This fellow seems fairly objective and has a comprehensive and ever growing list of tested filters.
You also mentioned that syn can provide greater protection and alllow the use of a thinner grade. I believe that the use of the 20 wt syn in the Hondas and Fords allows you to have your cake and eat it too. Milage plus acceptable wear. I believe that if I were the owner of one of these "fine" vehicles I would use the 10W-30 syn until the 5W-20 were available in syn.
Also, any Accord owners out there with service manual recommendations of 5W20: Is that dependent on ambient temperature? Does the manual specify a higher VI at higher ambient temps, or is the 5W20 for all driving conditions. I'm trying to become informed. Thanks.