CAT 3126B oil change interval

[chuckster]

I did end up changing my own oil and filter a couple of weeks ago. Drained out only 6.5 gallons even though the oil dipstick showed right dead-on the "full" mark before beginning. I know maybe a quart max is in the filter. When I put in the full 28 quarts (7 gallons) with the new filter, started it up and let it run for 5 minutes and then shut off the engine. Let it sit for 15 minutes and then checked the oil and was dead-on the full mark so no need to calibrate the dipstick...its accurate. My guess is there is a residual 1/2 gallon'ish in the engine that won't drain out the drain plug; no surprise there.

Ran the coach through a 1,200 mile trip afterward and checked the oil levels. Unbelievable how black the oil was already.