Why would oil pressure get higher?

[Chuck S.]

Re: Why would oil pressure get higher?

Actually, Dale, filters for Chevys never had by-passes until the 2006 Z06. In the past, Chevy build the pressure by-pass valve into the engine block/filter adapter.

When the Z06 went to the dry sump oil system in 2006, it used a different oil filter (PF48) with the pressure by-pass valve built into the filter. All Corvettes changed to that filter in 2007.

People changing their own oil/filter on C6 Corvettes should stay on their toes. While the new filter (PF48) is supposedly not interchangeable with past filters (PF46, et al), the two thread sizes (13/16" vs. 22mm) are very close...I guess I'm not convinced a dedicated, enthusiastic lube monkey couldn't make it work.

[Dale S.]

Re: Why would oil pressure get higher?

My recommendation for brand of oil at my Auto Parts store was always the same CLEAN OIL !!! Dale PS.The Fram people used to recommend changing the oil 4 times a year regardless of less miles. D. PSS this was in the 60's Chuck.

[Chuck S.]

Re: Why would oil pressure get higher?

New Corvettes have an engine oil life monitor...an on-board computer program that counts the rpm, the number of start cycles, temperature, and a bunch of other black box parameters to calculate the percent oil life remaining.

The owner's manual tells you to change the oil when the DIC (Driver Information Center) says it's time...some of those owners are going to 10-12K miles. GM is now guaranteeing those engines for 100K miles. When those owners DO change the oil, it's coming out BLACK...but, most people know you can't tell much about oil condition by how it looks.

I guess I'm old fashioned...even as a former maintenance engineer (experience = reliability + minimum operating expense), I have to change oil/filter at 5K or annually whichever comes first. But, I have learned one thing about discussing oil changes on internet boards: Opinions about oil changes are like, er, noses...EVERYONE has one; and they resolutely believe it is the absolutely only right one in the world.

[Duke W.]

Re: Why would oil pressure get higher?

GM also has a one year limit on the oil life, regardless of what the oil monitor says. This is a warranty requirement.

Annual oil/filter changes or every 5K miles, WHICHEVER OCCURS FIRST with CI-4 oil is a good interval for vintage cars that are not driven daily.

If you store your car during the winter months, change the oil and filter immediately prior to storage.

Duke

[Clem Z.]

to explain about the oil filter bypass missing

or stuck open. the oil filter is a restriction which lowers the oil pressure some BUT if the oil filter bypass valve is stuck open or missing the oil does not go thru the filter,it takes the path of least resistance thru the bypass hole, and you will see a slight increase in oil pressure on the gauge