I've got the Factory Service Manual (FSM). It has two schedules in it.
Schedule A is 'change engine oil at 7500 miles (12000km)or at 6 months' and 'replace engine oil filter on 2.4 liter engines'. At 15000 miles (24000km)or 12 months it says 'change engine oil and replace engine oil filter'. Basically, schedule A is change engine oil every 7500 miles or six months, and oil and filter every 15000 miles or 12 months, UNLESS you have the 2.4 in which case it's oil and filter every 7500 miles or six months.
Schedule B is at 3000 miles (5000km) 'change engine oil' and 'replace filter on 2.4 liter engine'. At 6000 miles (10000km) 'change engine oil' and 'replace engine oil filter'. and so on and so on. Basically schedule B is oil every 3000 miles for any engine. Filter on the 2.4 liter every 3000 miles and filter on all other engines every 6000 miles.
It says schedule A is for normal operation, and schedule B is for - frequent short trips less than 5 miles, frequent driving in dusty conditions, frequent trailer towing, extensive idling, more than 50% of driving is at sustained high speeds during hot weather, above 90f, or use of E-85 (ethanol fuel) in the 3.3 liter engine.
Holy cow, you'd think a lawyer wrote this stuff. I guess Chrylser had GREAT fatih in it's oil filter to recommend 15000 and 6000 mile intervals and every other oil change.
Oh, by the way, let your brother-in-law know that the all wheel driver power transfer unit fluid should be changed at 15000 miles, and the all wheel drive overrunning clutch and rear carrier fluid should be changed at 21000 miles. Tranny fluid is every 15000 miles.
[ March 20, 2004, 03:48 AM: Message edited by: rcy ]