1968-2006 Oil Filters

[Paul B.]

Joe, isn't the...

WIX 51069 be the one for the '68-'96 cars??? Tried looking up 51060 and it had current Chevy trucks and Hummer as usage???

[Joe L.]

Re: Joe, isn't the...

Paul-----

Yes, the 51069 is the direct equivalent of the PF-25 which is the filter used for 69-91 Corvettes (and, much later for other models). However, I've always used the old PF-35 or current PF-1218 size filters. The 51060 and 51061 are the equivalent of the PF-1218. Since the PF-1218 is shorter than the old PF-25, it turns out that it's only about 1/4" longer than the PF-25 size.

Since none of the Wix filters are going to be "correct", I say use the filter with a little more filtering capacity. I don't know if it's necessary, but it can't hurt anything (however, I don't recommend using any filter longer than the original PF-35 length; longer filters represent a risk for road hazard damage and, in my opinion, it's just not worth that risk to get even more filtering capacity).

Of course, if one were going to strip all of the paint off the Wix filter, repaint it, and re-silk-screen it to "mimic" one of the AC filters used over the 69+ period, then the Wix 51069 would be the one to use. I don't intend to get into anything as crazy as that, but some folks might.

[Michael F.]

Re: Additional Filter Photo/UPF???

what does the UPF mean/stand for, the zo6s came with the pf44, is that the same thing??? thanks.

[Clem Z.]

the UPF uses synthetic media which has

smaller pores that filter finer. they can do that because unlike the paper media in regular filters that would swell shut when they get moisture in the filter. i once built a all aluminum BBC race engine from a after market block that had porous walls and the oil pan would pick up about 1 quart of water every race night. with a regular oil filter the oil pressure would drop from 70# to 40# because the filter paper was swelling the pores closed. if i did not have the filter bypass blocked the pressure drop would not have shown on the gauge. i talked to bill howell at GM about the problem and he sent me some PF35L filters which are the synthetic media and the oil pressure never droped even thought we would drain a quart of water out of the oil pan after the races. this engine is at least 30 years old and is still running today and still leaking water.

[Joe L.]

Re: Additional Filter Photo/UPF???

michael-----

The PF-44 is a conventional, cellulose fiber media filter. It was used in PRODUCTION for all 1997-2005 Corvettes. For 2006, it was replaced by the PF-46. The PF-46 also SERVICES all 97-05 applications, as the PF-44 is discontinued.

The UPF-44 is, as clem describes, a synthetic media filter. Synthetic media filters will trap contaminant particles which are smaller than can be captured by a cellulose fiber filter media. The "U" in "UPF" represents the term "Ultraguard" which was the Delco designation for this series of synthetic media filters. "PF" is the Delco part number prefix for all oil filters.

The UPF-44 can be used for all 1997-2006 Corvettes, Z-06 and otherwise. It cannot be used for ANY 2007 Corvette, though. 2007 Corvettes, Z-06 and otherwise, use the PF-48 filter. As far as I know, there is no UPF-48 filter available. Will there be one? I doubt it.

[Chuck S.]

Re: Additional Filter Photo/UPF???

Actually, all the LS7s (Z06) started using the PF48 with the 2006...that seems to be how the LS2 got hung with it. Because of the dry sump oil system on the LS7, there is no pressure bypass in the engine, so they put it in the filter. They standardized the LS2 to use the PF48 in 2007.

I'm like you, I would rather have the pressure by-pass in the engine than the filter. As often as I change my oil, the built-in pressure by-pass should be perfect for the life of the engine. Doing a shake-down on a new pressure bypass with each filter change is not a good idea IMO.

[Clem Z.]

the by pass valve is only there to protect

the engine in case the filter plugs up and you will never know when this happens with the by pass valve in place so i would use the PF46 even in the ZO-6 and 2007 LS-2,if the threads are the same, because you would see it on your oil pressure gauge. i had engine that i built and after the camshaft break in i told the owner to change the oil filter because it would be plugged shut with moly kote after the oil cooled down. the next day he called and said he had no oil pressure and i ask did you change the filter and he had not. if this engine would not have had the oil filter by pass plugged he would have never know the filter was plugged. i plug the oil filter by pass on most all my street cars because till the oil pressure equalizes on both side of the buy pass valve unfiltered oil goes thru the engine

[Chuck S.]

Re: the by pass valve is only there to protect

The threads ARE different, but close enough IMO to possibly be a huge PITA if someone gets the wrong filter and isn't sharp enough to not try and force it: PF46 has 13/16" NC, PF48 has 22 mm.