If you have an extended warranty, as some of us do, then you have to keep good records of the oil/filter changes. Keep your receipts in a file along with a receipt for your filter. There are cheap logs that you can buy at local RV shops, where you can record your milage and oil changes.
Also, I usually use synthetic oils, but have switched to regular high grade petroleum oils, per recommendation of my trucker friends. I record the oil type and amount in the log.
The oil drain valve is a god-send.
07 TM 40D;ISL 450 Cummins(upgraded). Very happy w/coach
Gnarly toad to scoot around.
Geocaching, hiking, fishing, National Parks, Civil War sites.