Doing the appropriate thing, for my driving load, from the owner's manual. Every 7.5k, for now.

 

I didn't answer the poll because it doesn't have the correct choice for me: It depends. Got 22k and 25 months from the last sump. That's with a big bypass filter and oil analysis. Unfortunately, the Rotella T-Syn did not hold up for me like I expected. So I will change it anually until my supply of that runs out and try something else.

 

I use the rotella syn oil in every diesel I have with a turbo. In the rabbits I use regular dino oil. The truck I usually hit somewhere after 10k and before 12k. which is about 2 times a year sometimes 3. Its due again now.

 

I run my truck like a hot rod diesel, so I change it every 3000 miles with Rotella and a factory filter.

 

10K Using Amsoil

 

depends on what I am doing.. spring/summer, if towing heavy loads thru the Flint Hills and/or in dusty areas( and I do mean DUST) I might change it after every trip and clean my air filter out with compressed air also.. If i am driving hwy/paved roads not doing a lot of heavy work, maybe at 10K if I remember, as soon as I think about it if I dont ...

 

Call me crazy but I filled mine with the 25K Amsoil so considering how much I drive my mess these days, it'll be a very l o n g time before the next change.

 

I know the feeling. You might be like me and change it, at least the filter, prematurely out of guilt...
"2 years, only 13K...heck why not..."
Its a good excuse to get away and turn a wrench on your truck, ya know, to relax, even if its only a drain plug...

 

Oh I still change the filter at the recommended interval.

 

Every 10K w/ synthetic Premium Blue.
I took a sample last oil change but never sent it in to Blackstone .

Many variables here:
Synthetic vs dino
High mileage vs low mileage engines
Service duty
Driving habits
Filtering systems
Oil Analysis
etc, etc

 

Wouldn't it be easier for them to test the oil if they actually received it?

 

Guess that's why I haven't received the results yet...

 

About 20,000 miles with amsoil,and oil analisis shows this to be good. Do have a bypass filter also. This is about a year of driving for me on this truck.