the cummins 10,000 mile oil change interval

[The motor guy]

I noticed a lot of guys with a cummins turbo diesel frequently run 10,000 miles between oil changes. I know the cummins turbo diesel is easy on oil, but isn't that a lot? I guess if you run down the highway all the time it's fine, but if I did that my truck would have like 600hrs on it before I reached that mileage.

 

[Nick1994]

10,000 miles isn't really that wild of an OCI, especially on a diesel.

Do a UOA and find out. If you're able to extend your interval, with as much oil as that truck takes it will easily pay for itself.

 

[skyactiv]

I'm a semi mechanic at UPS. The yard shifter trucks that move semi trailers around the lot at sort facilities have a Cummins 6.7 in them. It is a lower output version of whats in the Ram truck. The engines hold up for 25K hours with 500 hour PM's. A word of advice, don't let modern diesels sit and idle like diesels of yesteryear. Modern diesels put a heavier burden on the emissions system when idling.

 

[The motor guy]

Originally Posted by skyactiv
I'm a semi mechanic at UPS. The yard shifter trucks that move semi trailers around the lot at sort facilities have a Cummins 6.7 in them. It is a lower output version of whats in the Ram truck. The engines hold up for 25K hours with 500 hour PM's. A word of advice, don't let modern diesels sit and idle like diesels of yesteryear. Modern diesels put a heavier burden on the emissions system when idling.


Do they still have the 3 gallon sump or is it bigger?

 

[BrianF]

I cant comment on the first gen 6.7's, that used just EGR and DPF but the 2013+ with SCR seem to do quite well. It is still the 11-12 litre sump. Ram now says for 24,000km/15k mile changes.

I am just starting UOA on my ISB6.7. My first test was 48,000km on the truck, 24k on the oil. I changed the FF out at 24k so there was remnants of it in the sample. My wear metals were high, as they should be but I was more interested to see how the oil held up. It did fine.

Notable was that soot was less than 1%, which seems normal on other UOA I have seen. My fuel was under 3% as well and the oil was fine.

As I gather some more data I plan to stretch the index out further.

 

[Capt]

A family member has a 2015 6.7 Cummins and manual says 15,000 miles/ 6 months. 15w-40 warm and 5w-40 synthetic cold temps. He goes by the OLM and usually goes off around 14,000 miles. It does do some idling so I believe the OLM subtracts miles for higher engine time ratio..

 

[mattd]

We have several 8.3L ISL's in our pumpers for the city and they are not the best with longetivity. Cylinders worn by 12,000 hours causing high crankcase pressure. They have 6 month PM services and hold about 30-32 quarts of oil. They are fed a diet of 15w40. The emissions system is also not that great, several DPF related issues along with their controls. Some EGR related problems but those are few and far between. Granted the service they see is severe.

I have little experience with the 6.7 Cummins, but the 6.7 powerstrokes seem to be holding up well in Thebes rescue chassis. They average about 4000 hrs/year. The last engine I rebuilt had 25,000 hrs on it. They get PM's every 4-6 weeks

 

[mattd]

That is supposed to say "the" not "Thebes"...

 

[oil_film_movies]

10,000 miles is for woosies. How about 100,000 miles? "Mobil Delvac 1â„¢ Advanced Fuel Economy 5W-30 meets and exceeds the longest oil drain interval requirements defined by major manufacturers, offering protection during extended oil drains up to 100,000 miles." -- https://www.mobil.com/English-US/Co...obil-Delvac-1-Advanced-Fuel-Economy-5W30
I was shocked when I read that! Only way I could see it is if you ran a bypass oil filter & used the system where oil is fed to the fuel injectors (oil topped off a lot).

 

[Donald]

Remember there is 12+ qts of oil in the oil pan. With synthetic oil 15000 is fine, but one needs to do UOA if you are going over the manufacturers OCI.

Some have large bypass filters also.

But believe me no one is risking a $20k engine if they were not confident they could extend the OCI.

($20k is a guess for the cost of a new 6.7 PSD engine.)

 

[mattd]

Originally Posted by Donald
Remember there is 12+ qts of oil in the oil pan. With synthetic oil 15000 is fine, but one needs to do UOA if you are going over the manufacturers OCI.

Some have large bypass filters also.

But believe me no one is risking a $20k engine if they were not confident they could extend the OCI.

($20k is a guess for the cost of a new 6.7 PSD engine.)


A drop in engine intake to pan with turbo is about 15k$

 

[The motor guy]

Originally Posted by Donald
Remember there is 12+ qts of oil in the oil pan. With synthetic oil 15000 is fine, but one needs to do UOA if you are going over the manufacturers OCI.

Some have large bypass filters also.

But believe me no one is risking a $20k engine if they were not confident they could extend the OCI.

($20k is a guess for the cost of a new 6.7 PSD engine.)



True but it's also a bigger motor.

 

[DoubleWasp]

I'm doing 25k OCIs with my 6.7s. No issues.