Desert Nomad

Usually the oil filter box has an illustration on how tight it should be. Normally 3/4 to 1 turn after seal touches the base. I always fill the filter with oil and lube the seal to.

3X2

Lots of luck on that happening. OP stated it was changed a year ago. I doubt any place would "warranty" it.

Secondly, the filter pictured is not the correct AC filter for a LS7. That may be the only reason to bitch. I've seen many dry sumped LS engines come in with the wrong filter.

The oil filter seals directly to the oil pan. the only part replaceable is the threaded section that screws into the pan casting or the oil pan itself.

GOLD72

Please explain to me how every LS7 engine built for model years 2006 thru 2008 came equipped with a standard blue AC Delco PF48 filter?? I personally owned an 2006 Z. Why is because the black UPF48R wasn't made and introduced until MY 2009 and was made necessary because of the ZR1 LS9 engine with its higher oil pressures. Nothing changed at that point with the LS7 engine other than it got the same new and bigger dry sump tank as the LS9 plus it got the LS9's liquid cooled rather than air cooled oil cooler. 2009 and later LS7 and dry sump LS3 engines all got UPF48R filters for GM's supply chain convenience reasons as they were all built at the Hi Po Wixom engine build center along with the LS9 that needed the UPF48R. GM was more than happy with helping AC Delco sell more UPF48R filters as there is a rather limited population of LS9 corvettes alone out there (mine being one of less than 4800).

GOLD72

If the OP's service receipt shows a filter part number installed that is actually a 44 or 46 series filter and that is indeed what is installed in that mangled mess now, frankly warranty won't play into this at all IMHO. An error is an error no matter how long it takes to discover. That thread pitch is wrong for the LS7 and is the direct cause of this huge MCF.

3X2

Looking at the OP's picture, it shows the coolant over oil heat exchanger. Going by what you said, it should have a upf48r (black) oil filter from GM, not a blue pf48 filter (assuming the filter pictured is a pf48). I pointed it out that it was the wrong filter. Yes, a 48 will work, but it is not the correct filter. So, that tells me someone, somewhere along the way used a non upf48r filter. Without re reading all the posts, I don't remember where the OP said which filter is on the car. I use the 48r on all factory dry sump C6 engines that I work on- unless it has an aftermarket oil pan.

3X2

The hole in the 48r is larger than both the 44 and 46. How do I know? I'm in the process of replacing a blown LS7 and tried all three filters. Of the three only the 48r fits. A pf48e also fits

GOLD72

Actually you are wrong. The mounting hole bolt diameter is the same for all 44, 46, and 48 (including PF48, PF48E, UPF48R) series filters. It is the thread pitch that was changed for the 48 series filters so that the 44 and 46 could not be used interchangeably where a 48 is needed. Reason being is the LS7 block was designed without an integral pressure relief device. The pressure relief device was moved to the 48 series filters. There is no pressure relief device inside the 44 and 46 series filters. The LS1, LS6 and the earlier (05 & 06) LS2 engines all had pressure relief devices in the block. Yes any 48 series filter will easily mount to an LS7, LS9, LS3 and 2007 LS2 engine. I and my son have owned all of these. But you can't mount a 44 or 46 series to any of those forementioned engines that require 48 series due to the thread pitch difference.

GOLD72

That has been discussed here hundreds of times over the past 7 years. GM is just trying to help AC Delco sell more UPF48R's as there isn't enough LS9s to create the aftermarket demand for that filter plus supply chain management for only one filter at Wixom for all dry sump engine builds is a benefit for GM.

olddragger

make a way of hooking up a little impact gun on it---if it is not too late.

3X2

IF you are correct, there is still no way to install a non 48. One would have to force it on. For sh*ts and grins, maybe I'll try to do so on an extra ls7 pan I have laying around. Using my cheap dial calipers, there is a difference in hole diameters by about 1mm.
What pressure relief are you referring to? AFAIK, all LS whatever in Corvettes have what I call a barbell that is in the oil galley at the rear of the block that unseats if the oil filter clogs.

Nowanker

Just looking at an LS7 on a stand now... it does indeed seal right up against the oil pan. Caution if using an air chisel or even a hand chisel! Replacing the pan would suck in a major way...

gsflyer2011

Agree. Once i had someone tried to change a flat tire and tightened on lug nut so bad it had to be torched off. This is sounding more and more like that. Hell, i had graduates from A&P school turning nuts clockwise and not knowing why it wont come off.

LMB-Z

I just hope the OP gets it off without any damage to anything. At this point in time, it really doesn't matter what filter it is...it could be a 98e802dftx2x made by NASA. It has to come off. Good luck.

GOLD72

if that is the case for LS7, LS9 and LS3 engines, then it means that GM has told the public a big lie as to why the PF48 filter was introduced to replace the PF44/46 filters ten years ago starting with the LS7. BTW, I am only speculating that the OP's filter series is wrong as I cannot imagine an oil filter that messed up to remove without a drastically huge mistake being made with the install.

GOLD72

After looking at some naked oil pan photos, I agree that is the case. Someone earlier had inferred it was separate and I assumed that it might be true. The biggest disaster will be to accidentally damage the filter mounting pad on the pan and have to replace the entire pan.

3X2

I'll try to explain it as best I can as I understand the oiling system. What I call a "barbell" sits in the oil galley behind the rear cover. It has an o-ring, #14. When installed it sits forward in the galley bore sealing the bore at the o-ring area directing pressurized oil to go through the filter, exit the filter on the back side of the barbell sending oil to the mains, rods, cam, lifters, etc. If the filter clogs, collapses, or whatever to prevent flow through it, oil pressure on the front side of barbell causes it to move rearward opening the galley that feeds the mains, etc, bypassing the filter so the motor doesn't starve for oil. I guess dirty oil to the bearings is better then no oil. I'll assume none of us lets our filter get to that point. I believe there is also a oil cooler bypass in case the cooler clogs weather it is the air over oil or coolant over oil style.

Those blue filters are very thin walled and I've bent, crushed, and punctured quite a few taking them off. Too tight? Dry o-ring on install? Who knows. For whatever the reason in this case, I hope the OP gets it off with damaging the oil pan and suggest using the upf48r filter and get the correct filter socket.

Nowanker

Building an LS7 now... the barbell isn't designed to move in the bore. Rear surface of it is flush against the rear cover plate, so it has nowhere to go. Looks to me that its sole purpose is to simplify machining of the block, making the oil galley to and from the filter one straight bore.
$.39 plastic piece simplifies the casting and replaces one or two ops on the machining line.
The filter itself might have the bypass, many do...

Dellis

I just went through this with my C-5. Tried some of the same tools as you with similar results.

What worked for me is a filter cap placed over the bottom of the filter. I then drilled 3 screws into the cap and the bottom of the filter. After the cap was affixed to the filter, I was able to unscrew it.

I know you said a cap will not fit now but maybe there is a larger size you could try?

Mike44665

Gold72,

Thread pitch. When installing the new filter, if you could not turn it enough to engage the gasket to the mounting surface by hand, one would have to be a CFI to go any further using whatever to get er done. My $.02.

shane p

I think all LS oil pans from LS1 up have the oil filter boss built in, don't mess that surface up or you will be replacing the oil pan, none of them screw on the block. I believe the plug in the back of the block is that, just a plug or a restrictor, some engines have multiple plugs when they drill the oil holes they have to run into other holes to get oil everywhere so in doing so some need to be block so it doesn't look like a water sprinkler. If the thread pitch is different on the filter it will not go on by hand and maybe even galled so bad you cant get it tight. Someone would have to be a real idiot to do that and if that's the case I would be taking the filter somewhere and shove it up someones rear end.