I am NOT a self proclaimed "oil technical expert." I do know a little about oil and have taken apart a LOT of engines and seen the innards of those with frequent oil changes and those without.

To set the record straight, I have never ruined an engine due to "negligence." I have, however, ruined a few by MISTAKES that I committed. Have you ever made any mistakes? None of the engines that I have ever hand grenaded were oil related failure!

Now, since you have been so insulting as to question my ASE Master certification, you are totally free to verify said certification with the ASE organization. If you will private mail me I will even supply my ASE ID number. I have not been a professional mechanic for over 30 years, but I have enough time doing so that I was qualified to take the tests so I did. At the time I did this, my industry was really shaky and I thought I was going to have to resort to twisting bolts for a living again, so I prepared for it.

EVERYONE on this forum is indeed free to draw their own conclusions and form their own opinions. I have mine and others have theirs. When have I EVER FORCED anyone to do ANYTHING?

IT DOES NOT matter to me if anyone changes their oil or not. You are free to pour Maple Syrup in your crankcase and run it as long as it will run if that's what you want to do.

When I melted down my daughters engine when changing the IP, I Posted the results of that incident, at the cost of my own embarrassment for only ONE REASON. That was an effort to prevent others from making the same mistake. If you want to bring it back up and rub my nose in it, then go ahead if that makes you feel like a better person. Would you prefer that I keep my mouth shut and just let everyone else make the same mistake?

You and 240Joe apparantly are from the same mold. In fact, I'm not sure that you are not 240Joe with a second account.

Whoever you are, go ahead and throw insults all you want. You are free to do so. Have I ever insulted YOU?????

There's probably some truth to that dealer theory, but on every gasser I've owned sofar (approx. 20) of various mfr., the engine oil would stay the new light brown color until somewhere between 2K and 3K miles. After 3K it was black, which says to me that it's reached an unacceptable contamination level. Hello, time to change the oil.
So it seems logical that there is something more to the typical 3K mile change recommendation than aspirations of financial gain.

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'83 300D Turrrbo 295K miles

i don't have a clue why you choose to denigrate larry bible. he is one of the most if not the most knowledgable members of this site. he is generous and honest to a fault.

i am a believer in changing every 3k if i am using dino oil, five or six if using synthetic. i am from indiana.

i am another person who does not hesitate to post things i have done that are embarassing for the reason larry posts....if it might help someone else avoid trouble.

this forum is just great. when larry and i (and a host of other fifty and sixty somethings) were coming up, we only had our friends and family to learn from. you young guys have the opportunity to learn from our many mistakes. kindof like having a hundred immediate family members with actual hands on mercedes fixing experience.

you don't realize how good you have it.

as larry said, put molassas in your oil sump if you like.

but as for me, i will continue to change it at 3k on my older cars with dino and 6k if synthetic.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Yeah that doesn't mean much. I prefer lab results, 10k miles is fine with most engines and synthetic oil.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200

get em larry,
the man has almost 10,000 posts, that means something in my book

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82' 300SD

I couldn't agree more.

I'm sure I'm one of many who recognize how great this board is, and how much more difficult life would be without it. I didn't know much about cars in general, and practically nothing about diesels, before coming to this forum. Even with the factory manuals, I wouldn't have a chance maintaining and repairing my car myself, and the nightmares I've read about the money people have spent to have someone else "fix" their car for them make me realize even more how valuable this board is. The Internet made this board possible, but the people behind it makes it what it is. The collective experience and expertise available on this board is invaluable. Hopefully, as I learn, I'll be able to contribute to this expertise. Until then, thanks to everyone who generously takes the time to teach people like me. We appreciate it!

I am almost sorry I started this discussion. It started out fine with people giving their opion. That is what I wanted. If we all listen and learn from others we will be much better off.
I personally have been working on cars for most of my life. For the last 23 years I have run my own shop and have seen a lot. I have seen the inside of more engines than I can remember. I do know that often I can tell which cars and engins belonged to traveling salesmen. The high mileage engins that were maintained on a regular basis are usually clean inside if they were maintained as recommended. Even the ones without proper maintaince were reasonably clean inside. On the other hand, the ones that were driven by "the little old lady only drove it to church on sunday" cars were gummed up inside and the life of the engine was shortened to 40 or 50 thousand miles.
These engines are also maintained as recommended. The problem on the second car is the maintaince schedule is different if the car is driven in severe conditions. People seem to forget to find out what that actually means.
Most think it means if they pull trailers or drive at high speed all the time, carry heavy loads, etc. It really means the car is driven mostly in city traffic, short distances, etc. If you don't believe this get out your owners manuel and read the fine print.
You have heard if from more than one that has actually seen the inside of an old engine and knows what can happen if the oil is not changed as often as it should. Now lets get back to the question of oil changes for cars that are run in extreamly severe conditions, in the humid south east, short distances, low speed, 90% of the time.
Any one else have any suggestions for these conditions?

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84 500 SEL (307,xxx miles)

As a perfect example to back up what you are saying (and I'm sure you've seen a few like this too) I bought a low mileage 70 1/2 Falcon one time from literally a little old lady. I bought it because it was fun to drive and it was a total rarity. In mid 1970 model year when the Maverick came out, they stopped building the old Falcon. They took the name and put it on the cheapest trim level fairlanes.

The car had a three on the tree and a 302 and was really quick and fun to drive. She had kept the car put away when not driving and she didn't park at an office or something in the heat, so it was cosmetically gorgeous with a little over 30,000 miles.

She lived in a town of about 7,000 people and I don't think the car ever left town very much. It cranked and ran fine, but smoked a little. I bought the car cheap because I thought it would make a good work car at the time. Once I started driving it, I found that it sucked oil like a pump jack.

When I pulled it apart it was not as gunky as one might think, but it was worn OUT. I took it apart thinking I could rering it, but I had to bore it, turn the crank and the whole nine yards.

She claimed that she had kept the oil changed and I believe her, but I think she was doing it by mileage and probably by the high mileage recommendations of the time.

One of the morals here is that mileage alone is not a good used car barometer.

I think we're finally getting to the root of the discussion. You are partly basing your 3kmiles oil change philosophy on data you collected in the 1970s. I agree that just because the data is old doesn't mean it's not still valid, but only if the conditions are the same. THEY ARE NOT...NOT EVEN CLOSE!

1. Engines made in the 1960s and 70 were mostly made with sand casting and a poor job of cleaning out the sand was done. The results should not have been surprising.
2. The poor choking system on the carbs almost guaranteed that the engine would run very rich at times... to the point of washing down cylinders. Fuel injection has pretty much eliminated that issue.
3. The oil was 1970s quality.
4. There were a lot of inferior engines built in the 1960s and 70s, mostly by American manufacturers.

I had a 1979 GM vehicle that I changed the oil religiously at 3kmiles and ran 15k of highway miles per year. This should have been ideal running conditions yet the engine was pretty much shot at 110kmiles. It suffered from almost every wear issue it could have.

Was that because I wasn't changing the oil every week? I don't think so. I think it was a poorly designed and manufactured POS. I could have had a oil tanker run next to me 24/7 and feed it fresh Penzoil and it still would have gone to sleep at about 100kmiles.

Things change. Average vehicles now get 150-200kmiles, and many of those die only because of overheats that could have been prevented with a little cooling system maintenance. Engines are made better. Fuel injection is great. Oil has radically improved.

Putting it all together means just about everything you learned about cars from the 1970's doesn't apply anymore. But it's easier to hang on to stale beliefs than to analyze data and formulate new ones. And the oil change places and parts stores don't help the situation.

Just driving to work this morning I heard an autozone commercial running an oil change special for 11 or 12 bucks, and they stuck the 3k mile oil change lie right into their ad.

And they do that because it sells oil, not because it should be changed at 3kmiles.

240Joe

Aren't we getting bored with this yet?

Hey, that was Joe's best post ever. Little in there to disagree with.



Tim

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2009 VW TDI Jetta Sportwagon 172k miles (rear-ended harder than Elton John on 8/4/13. Total loss)

1991 Volvo 240 142k miles (T-boned by a stop sign runner. Total loss)

I stopped reading them about a year ago.

My point in the post about the old Ford, had nothing to do with anything of the seventies and EVERYTHING to do with the need for oil changing by time on an engine that takes short hops. That was true in the carburetor days and it's true today.

Water is a byproduct of the combustion of gasoline, not diesel.

Again, we are talking about diesel engines here. More specifically, our Mercedes diesels. Short trips on diesel engines is not as hard on the oil as on gasoline engines. Short trips are not good for other things with our diesels but that's not the point.

Extrapolating any oil related information from information gained on a 1970 ford gasoline engine is pure fanasty.

The fact that you attempted to use it as a reason for your current 3kmile oil changes tells us plenty.

But as I said, your mind is made up and you continue to preach to the newbies how 3kmiles changes are the greatest thing since sliced bread.

And that is wrong.

240Joe

240, let it go. Seriously. This little pissing contest is ridiculous.

You don't think oil should be changed as often as Larry Bible does. Okay. We get it. He has his reasons and you have yours. The choice has been clearly laid out for other members to make.

I would find something else on which to launch a crusade.