Amsoil longevity

[1sand0s]

If you look at the signature, you will see how many miles my beast has covered.

It got its first oil change at 1700 miles when new. Amsoil 15-40.

The next one came 6000 miles ago.

Do the math.

No joke!

We are converting my truck from a matic to a standard transmission.

We noticed the rear seal was starting to weep a little oil when the trans came out.

So, we checked the thing to see if the bearings were getting loose and ruining the seal... . could need new bearings, right? It is to be expected when you are getting near the 400,000 mark... Amsoil or not... right?



It was within new limits.



I repeat, a motor could leave the factory looser than mine.

The seal has just seen too many revolutions. The bearings are fine.

376,000 miles on one oil change with filters every 50,000.



(I think you can let yours go a bit longer)

 

[Cliffman]

Wow, that is impressive. I know this has been discussed before but I would like to re-address it just incase there’s some new data. What is the difference between the 5-30 and the 15-40 besides the obvious? I know the 5-30 nets you slightly better fuel mileage but what else?

 

[PLaFrombois]

Cliffman

The real difference between the 5W-30 & 15W-40 would be the mileage. We've seen in testing Class 8 trucks, mileage increased 3-5% just with changing oil. Low temperature fluidity is a benefit for year round use, especially for those that live in cold climates. It is also convenient for those accounts that have multi-vehicle that are both diesel and gas engines. This eliminates the need for multiple oils in the shop, and possible mistakes of wrong oil to an engine. The 5W-30 has a higher additive count for soot control and wear metals content. The oil is protecting the engine, but at the same time it's cleaning the engine. This is where some have seen a higher metals content in their oil analysis. After a certain amount of time with mileage and filter changes, these wear metals will level off and remain steady.

Both are excellent products, and you gain the advantages of being synthetic from both oils. I usually tell people who live and mainly drive in the South/SouthWest the 15W-40 would work the best for them, just because of the hot conditions, and you wouldn't need the oil to flow at -0 degree temps.

But as I said in my earlier post, whichever oil you choose and how often you change the oil/filter has to be what your most comfortable with.

Paul