Originally Posted By: VR1
Honestly, lexus114 Pennzoil might have changed in these last few years but, I have seen way to many engines left dirty with sludge in the bad cases and varnish in most cases. I understand that any oil not changed regulary will sludge due to oxidation and what not but, if your changing your oil every 3 to 4k and are using the correct oil as far as the API rating and viscosity I don't see how any engine should have any dirt in it whatsoever except for what in the oil itself being held by the dispersants until the oil gets changed out. Call me crazy or old school but, I don't give second chances. Fool me once shame on you fool me twice shame on me.
Funny, I've never had any engine with varnish or sludge and have used mostly Quaker State and Supertech oils.
Sounds like you didn't keep up on your maintenance.