sounds like a checkvalve issue.
Oil Additive
Melting Slicks
Joined: May 2018
Posts: 2,091
Likes: 600
From: Question Government
Intermediate
Joined: May 2019
Posts: 43
Likes: 7
I'd probably suggest ditching that Fram filter. Cut one open one day and you'll see why. Try a WIX.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
The deal is anti drain back valve to reduce oil from leaking down. Fram came out with a filter with check valve before GM. If you have basically a stock engine PF1218 or equivalent it's the higher capacity truck filter. Wix does make a version 51060XP.
Melting Slicks
Joined: May 2018
Posts: 2,091
Likes: 600
From: Question Government
Isn't a check valve to prevent drain back in a horizontally or upside down mounted filter??? The '96 LT1 has an oil filter position that holds the oil in it, vertically mounted.
Last edited by RetroGuy; Jun 2, 2019 at 02:29 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Pro
Joined: Jun 2018
Posts: 532
Likes: 104
I would think all oil filters have anti drainback valves today. In any case if you changed the filter and it is still happening, it is probably not do to the filter, more likely a bad oil pump or gunk in the engine which is delaying pressure getting to the lifters.
I don't really think there is any problem with FRAM filters, or any other filters, as long as you change them. I have yet to see any oil analysis results showing one filter being better than another over a normal oil change interval.
People complain about the cardboard end caps, but several oil filter companies claim they bond to the media better than the metal caps and leak less around the joint between the endcap and filter media. The media also flows more cold than a filter with a metal barrell, meaning more of the oil is filtered and less bypassed when the engine is cold.
I don't really think there is any problem with FRAM filters, or any other filters, as long as you change them. I have yet to see any oil analysis results showing one filter being better than another over a normal oil change interval.
People complain about the cardboard end caps, but several oil filter companies claim they bond to the media better than the metal caps and leak less around the joint between the endcap and filter media. The media also flows more cold than a filter with a metal barrell, meaning more of the oil is filtered and less bypassed when the engine is cold.
Pro
Joined: Jun 2018
Posts: 532
Likes: 104
But there is oil above the oil filter in the oil galleries, that will exert a head pressure on the oil in the filter and without a drainback valve it will push oil out of the filter and back through the pump into the pan as those galleries drain down into the filter.
Last edited by auburn2; Jun 2, 2019 at 04:11 PM.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Around 1993-4 some Chevrolet 5.0 and 5.7 had a condition of cold start knock. It was attributed it to oil system leaking back. GM was recommending fram filters until AC Delco developed a filter to replace the pf 25 and 35.