I use synthetics in mine all the time plus prolong one time in My Jag I developed an oil problem. Problem was I did not know the gauge wasn't working. I blew the oil out of the car (drain plug came loose) and had less than a quart. I drove home from Columbus not knowing I found the problem and fixed it still shocked it didn't lock up. I figured the motor was toast but two years later and 50K miles more at 186,000 miles I took the Jag apart for a blown head gasket and the internal parts were still good. I rebuilt it with the same cam and crank. Still to tolerance specs. and no signs of significant wear. I'll pay the extra price and protect the engine My DeLorean gets new synthetic To me its worth it and so do all my cars ------------------------------------------------------------------------ eGroups.com home: http://www.egroups.com/group/dmcnews http://www.egroups.com - Simplifying group communications