07 Chevy 2500 H.D. with 8100 and Allison trans.

Status
Not open for further replies.
You could, but why? What's wrong with the OE spec? They're great engines that live a long life on the original specified or multi-fleet 15w40. They pull really hard but I've never met one that didn't consume a fair bit of oil.
 
Originally Posted By: Farmncraig
Would it be alright to use 15w50 synthetic oil in this motor. It only has 50000 miles on the engine.
Is the oil properly rated?
 
As long as it is CI/J/K, I can't see why not. I've seen one Chevy of the same year and engine for sale, for and astronomical price, considering it had 735k and no rebuild to anything. I was surprised.
 
20w-50 synthetic is a very common fill for that engine in marine duty. The engine won't care.

I would back off to a 5w-40 in the winter if you get super cold winters.
 
When we ran this combo in the Allison lab, we used Mobil 1 15W50 in the engines.
None of the many engines we failed were lube related problems, it was always broken pistons, rods, and valve springs. All of which were related to the high rpms the test cycle ran.
 
thanks and what do you consider cold winter I am in va, but have older dodge 5.9 gas and used it since I bought it used and no problem just like to use the same across the board. was worried small oil passages and would damage the 8.1 engine.
 
What does the owners manual say ? Mobil 1 10w-30 high mileage may work. It's hths number is thicker than standard mobil 1 10w-30
 
I used 15W-50 M1 in my big block 92 Suburban when I used to tow a race car around. (about 12,000 lbs w trailer,tools & spares) No problems, but it didn't get driven much in the winter & was always garage kept. If you're working the truck hard like I was, go for it. If not, your 10W-30 is fine.
 
My dad drives a 2002 with that engine/trans. Spends winters in Yuma, AZ, the summers in WA state. Carries a huge in bed camper. He runs Amsoil 10W30 all the time. Never had a problem. 140k miles and humming along.
 
Last edited:
Originally Posted By: Dyusik
As long as it is CI/J/K, I can't see why not. I've seen one Chevy of the same year and engine for sale, for and astronomical price, considering it had 735k and no rebuild to anything. I was surprised.

It's an 8100, which is a gasser, not a diesel. So, API SM/SN.
 
My boat has the same engine. Mercruiser used GM 8.1l longblocks and added a larger cam for the 425hp HO model. Running Mobil Delvac 1300S 15w40 at 25-30 hr oil changes. M1 0w40 also is a good choice. The early 01-04 8.1's had inferior intake gaskets that allowed oil to be burnt. Later 05+ 8.1's had redesigned gaskets that cured the oil burning problem.
 
My personal opinion is to use a good synthetic be it 5w/30 or 10w/30 such as Mobil 1 or similar. No need for a super thick 15w/50 which will just cost you a little power and fuel mileage while not returning any noticible protetection for those losses. If you really want thicker I would go the Mobil 1 0w/40 at the most.
 
Status
Not open for further replies.
Back
Top