LawrenceFromTorrance

Thicker oil will up your pressure but won't solve the problem. In fact it may hide it so I would stick the 5-30 until you can fully diagnose the problem.

crAzy

Yea I will consider that and keep running 5w30 like I have. I really think it is the filter. Plus spec still calls out 10psi for every 1k rpms. Still good.

JP426

You will get some oil draining out when you loosen the filter, not a whole lot but have a drain pan ready.

JetstreamGS

UPF48R is the correct filter you should use. It is designed specifically for the higher oil pressure of the dry sump engine. The filter, assuming you have the correct one, is not the problem.

I believe the early Z06 used the standard filter, however, the black R is the superior filter.

crAzy

Yep I have an 06. Possibly that is why? Filter was always blue and what was recommended both from autozone and O'Reilly.

JetstreamGS

That's right, blue is the standard filter that the early Z's used, however, they are interchangeable and the black one is what I would recommend.

pkincy

What is the difference between the UPF48R and the PF48 that can be found at all autoparts stores and dealers?

I did use a PF48 on my last oil change and noticed that the dealer had used one also (the one I removed).

I did find the UPF48R on Amazon and ordered 2 for garage stock.

Gary '09 C6

I believe the UPF-48R has a slightly thicker outer shell to assist with the increased oil pressure associated
with the dry-sump systems.