What Enables Such Long Intervals With Diesels??

[Danh]

All of this plus diesel fuel has some lubricating properties while gasoline is a solvent.

 

[Soft Cars]

Large capacity oil sumps are a big big help with engine oil life; that's for sure.

 

[ESP9935]

I just read where a trucking company with the help of Mobil and Cummins have gone to a 60K mile OCI and keeps the engine in warranty as long as they do oil analysis every 10K.
Is it the fact that the 'Big Trucks" have 20-40 gallon oil capacity and the fact that diesel fuel itself is oily that allows such long intervals whereas, gas engines have much lower oil capacity and the fuel itself isn't "oily"?

Extending Oil Drain Intervals With Mobil Delvac 1300 Super

A commercial trucking fleet utilizes Mobil Delvac 1300 Super to increase their fleet's oil drain intervals by 50,000 miles.

www.stern.co

I work for the maintenance division of one of the largest OTR carriers in the county.
They've been running 50K oil change intervals with Cummins ISX/X15, Detroit DD15 and Volvo D13 with Chevron 10W-30 Semi-syn and Fleetgard filters for years. The OEMS do not protest the oil change intervals.

Oil system capacity ranges from 11-15 gallons

 

[The motor guy]

My old 1989 400 big cam Cummins held 44 qts of Rotella T4 with a 12,000 mile OCI. My last tank of fuel in 1994 was $0.899 per gallon at 6.5 to 7 mpg. My how times have changed.

what do they get now? 5-5.5?

 

[The motor guy]

Large capacity oil sumps are a big big help with engine oil life; that's for sure.

I bet that would be detrimental if it was a short tripper.

 

[DGXR]

Show me a truck with a 40-gallon oil capacity.

 

[John105]

I was in a repair shop and was told the capacity on the tractors was 45 quarts and 60k oil change intervals. Since I got to walk around the shop and the parts bins, I said, oh, you use Baldwin filters? I heard they and Hastings were good. The svc manager said they're junk but we're cheap

 

[John105]

Show me a truck with a 40-gallon oil capacity.

bet it was supposed to be quarts

 

[MSCH]

what do they get now? 5-5.5?

my son was driving a rather new Kenworth T680 with the X15 and it averaged slightly more than 8 mpg... as my son said it would probably do better than that if he didn't let it idle the other 24 hours a day when he wasn't driving.

 

[FCD]

In Europe OCI's for large trucks are almost pushing 100k miles, there is even talk of soon going to 200k kms, 120k miles.

 

[The motor guy]

my son was driving a rather new Kenworth T680 with the X15 and it averaged slightly more than 8 mpg... as my son said it would probably do better than that if he didn't let it idle the other 24 hours a day when he wasn't driving.

Not bad. I thought they got crappy mileage with all the epa stuff