I have taken my coach to the same independent diesel repair shop for 6 years for service. They do all the local tour buses and a lot of OTR trucks. For an oil change, (26 qts), oil filter and complete lube it cost me $225. They check all oil levels and check the slack adjusters. I also get my coolant test kits from them to send to Cummins lab. When they serviced the generator it was $30 more for oil and filter. They also did the filter replacement on the Allison transmission but I had the filters so they only charged me for 6 gallons of Transynd oil and 30 minutes additional labor.