pyroManiac Loc: HIXSON,TN

In the 1930s and 1940s a car would go maybe 40,000 miles and need an overhaul. Now it is not uncommon to see one run for 400,000 or more. Oils are now much better as are engine materials. I wonder if Mobil 1 were put into a 1940 Chevrolet how long would it run. Does anyone know of such a trial? I have seen old cars restored to look better than new but they are usually only driven to and from car shows which tells very little.

BBurns Loc: South Bay, California

I have been a proponent of synthetic oils for almost 50 years.
I am a retired aerospace engineer as well as a prototype machinist.
I have used Mobil 1 in everything I have owned since it came out.
Anything that used oil got Mobil 1 installed. Dune buggies, Lawnmowers, Rototiller and about 6 other cars & trucks, I have lost count.
1985 Honda Accord SEi - 310,000mi.
1992 Cadillac Eldorado - 220,000mi.

Back around 1991, Corvette made Mobil 1 its official oil, to the point that if any other oil was used it would void the warranty.
Many manufacturers today, now specify a synthetic as the only recommended lubricant.
When I did side work, I always found that any engine I opened up that had used synthetic lube was much cleaner internally.

I am not a big believer in additives but I will mention one that I have used for over 20 years. AvBlend
It is the ONLY oil additive approved by the FAA for use in aircraft engines.

I am not pushing it, I am just saying that I use it and have seen very positive performance in my applications.

pyroManiac Loc: HIXSON,TN

This establishes that modern oils are I think for most part probably all good but the use in say a 1935
Ford unanswered. Someone who might have a vested interest in this might be one of the oil companies but rebuilding the 1935 Ford using original parts to answer the materials part might be not so easy.

JRiepe Loc: Southern Illinois

The owner's manual for my 2016 Mazda CX5 recommends synthetic oil only and that's the only oil that will be in it as long as I own it.

DirtFarmer Loc: Escaped from the NYC area, back to MA

I suspect that the engine materials play a part in the increased life. Certainly the oil is part of the equation.

cmc4214 Loc: S.W. Pennsylvania

Not only the materials, but also the accuracy of machining and balancing greatly affect engine life.

DennyT Loc: Central Missouri woods

Just my opinion but I believe that it a combination of better materials? Much much better designs .
As far as oil goes. Dont synthetic oils more than anything make up for consumers failure to change oil on recommended cycles .

We have all seen stories of an older car a rambler going 300,000. When ask the owner always says he maintained it religiously.

John N Loc: HP14 3QF Stokenchurch, UK

Much finer manufacturing tolerances and more efficient fueling also play a part. The oil might help the 1930's engine last a bit longer but it's still going to get diluted with unburnt fuel dripping into the sump.

Caribou Loc: St. Louis, MO

A friend of mine, a mechanic, explained to me once that the crankshaft bearings on cars from the 30s and 40s were babbitted. From what I understand that gave those bearings a limited life--maybe 50,000 miles at most before they had to be replaced. I don't know if today's synthetic oils would solve that problem.

StanMac Loc: Tennessee

I’ve not used anything but non-synthetic oils in my cars. My current daily driver is a 2004 Impala that has 365,000 miles on it, which I can only attribute to regularly scheduled oil changes, per the factory Recommended interval and the use of superior engine materials by GM in its manufacture. If I had started using synthetic oils at the outset, might I expect to drive the Impala for the rest of my life?

Stan

sodapop Loc: Bel Air, MD

Not a good idea to change to a synthetic in your case. Your engine, seals are used to what you are and have been using. Advice from a lubricant engineer

majeskiphoto Loc: Hamilton, Ontario

Just wanted to point out that Mobil1 is not a 'true synthetic' today like the original recipe years ago, not to say it isn't a pretty good oil. Secondly, it's not so much mileage that wears on an engine as much as the number of start and stop cycles an engine has to endure.

buckbrush Loc: Texas then Southwest Oregon

I was a transmission engineer for helicopters and was hired to improve the longevity of one model due to low time failures. The original model of Sikorsky used conventional oil and when I switched it to Mobil 626, a synthetic oil, the failures plummeted. The main failure culprit of most engines and gearboxes is heat. Regular oil will decrease its viscosity dramatically as temperature increases. Unfortunately, most manufacturers specify regular oil and therefore have problems. The best thing anyone can do is keep the regular oil cool as that is the culprit causing many failures. Cars that have very good cooling systems are likely to last longer because the oil viscosity will remain high. Synthetic oil on the other hand maintains a good (high) viscosity at least three times higher than conventional oil.
As far as additives, the mobil engineers I worked with said "if any additive worked, we would have added it to our oil", therefore don't add any additives.
It took the FAA a couple of years to approve using synthetic oil on the Skycrane but with the results of 2 years of sampling every 25 hours and documenting the exceptional benefit of synthetic oil they approved its use. It now being used by many helicopter companies as a standard gearbox lubricant.

buckbrush Loc: Texas then Southwest Oregon

I was also a tribologist and never had a problem switching from conventional oil to synthetic. It is always good to be cautious though.

FL Streetrodder

My two toys both are powered by 1970's vintage Chevy small blocks with flat tappet cams so I make a point of using engine oils with a high zinc content to minimize wear. Lucas Oil makes a "Hot Rod Blend" with the appropriate zinc content and several other companies sell a zinc additive that can be added to conventional motor oil.