View Single Post
Old 02-28-2009, 02:22 AM   #15
spinning wheels
Registered User
 
spinning wheels's Avatar
 
Join Date: Sep 2001
Location: Hacienda Heights, California USA
Posts: 474
Re: Recommended Oil for a factory 350?

From what I have been told, by a diesel fool, the motor oils intended for diesels, Rotella, Delo. ect.. Have a higher amount of anti sludge detergents. This is due to the by-product from the diesel fuels. From what he told me, they will clean the inside of a gasoline engine just fine, but chances are that sludge can find it was into the oil pump's inlet and start to plug it up.

Now, I am not sure if has his facts correct. But, I am not willing to test my motors to prove him right or wrong.

In my old '72 truck, I am running 10w-40. How many miles are on the motor is a mystery to me.

In my turbo volvo, it has been running on Mobil 1 since it turned 80k miles. Current milage is 250k and it runs just fine. Trans was rebuilt around the 125k miles, and has been using Mobil 1 trans fluid since. Rear differential also runs Mobil 1 gear oil.

One of my H-Ds has 60k miles on 15W-50 Mobil 1 and the newer H-D has 35k miles. Take into account, that they are air cooled, roller cam engines, and they tend to run hotter than water cooled engines. Amsoil 20W-50 runs great in these engines, but it is more expensive and hard to find.

The old stories of synthetic oil causing leaks, was due to the old synthetic formulas. The newer formulas do not have any noticeable affect on gaskets or seals.

Synthetic oils not only retain their viscosity better than dinosaur juice, it also hold up better under extreme heat conditions, and loads.

Consumer Guide did a test with NYC cabs running rebuilt Chevy 350s. It has been the most intense, non-oil company sponsored test. The conclusion, NO added benefits changing mineral based, motor oil at 3k miles. Mineral oil can last up to 7k, without engine problems, related to oil breakdown. The only benefits to changing oil at 3k, the oil companies will love you more.

I am not sure if the Consumer Guide, motor oil test is available online. It sure debunks a lot of old oil mysteries and stories.
__________________
'72 GMC custom camper 350/350
spinning wheels is offline   Reply With Quote