I am running Mobil 1 in my 04 sunfire with 95000 miles on it. I have been since 10000 and have been changing it ever 4,000 miles. I was wondering if any one can give me a clear difference as to what is different between the 2 and what one would be better for my car. I do about 90% highway and about 10% city driving.

Thanks Much

Josh

The EP is warranteed to be OK in your car until 15000 miles. I plan on changing mine at 10,000 this time. Maybe my 2nd change I'll consider 15,000.

But then you knew most of this anyway.

Yea I think that is the only difference. I run the Mobil 1 synthetic in my 04 GTO. I still change it every 4,000-4,500 miles though


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2000 Cavalier Z24 A4 Green Met.

The Mobil 1 original (non-ep) has less ZDDP and other additives in order to recieve an API certification, that little crest on the bottle, which means it is a safe oil for people with an engine warranty. The extended performance has massive ammounts of supersyn and thus ZDDP which disqualifies it from being an API approved oil, but on the other hand makes it very very strong and good for long drain periods like 15k.

The reason why this oil cannot be API approved is the high level of ZDDP that greatly extends the oils life can ruin a catalytic converter if it burns oil where it can effect it, on a engine that is not mechanically sound. This has yet to happen, but still, the guidelines have to be followed to be API approved.

The MOBIL 1 non-EP is dumbed down compared to the EP.