[blam]

I have a friend who says that it isn't uncommon for 18 wheeler trucks to get over a million miles. Also, they don't change the oil, just change the filter often.
Comments? True/false?

[bert]

My diesel uses synthetic oil.

A sample can be drawn and sent to Blackstone labs. They will test and return a report listing any contaminants and the need to replace the oil. I get a report annually but for a fleet tests can be requested at shorter intervals.

That is, like my doctor running the numbers on my cholesterol, A1c and PSA a pretty good dose of number running on the engine can predicate treatment.

[TweetEBird007]

Ran 2 18 wheelers, 3 14 wheelers, 1 26 wheeler (very short time). Had oil samples tested monthly and had air filters
cleaned as checks required due to dusty conditions and good bit of off road work. Oil filters were cut to test oil. A lot of difference in change oil requirements.

[cableguymn]

They use very fine by pass filters... they catch most anything.

But the do change the oil from time to time.

1,000,000 miles on a OTR truck is not unheard of. many truckers are keeping older trucks MUCH longer now due to all the EPA regs on the new ones.

[ROCKLOBSTER]

they don't change the oil, just change the filter often. Comments? True/false?

They change the oil. That's why there are 55 gallon drums of 15w40 diesel available.