4l80e leaking and draining

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yevgenievich

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A little late I know but, best thing I have ever done to rid myself of transmission leaks was getting a lubelocker transmission pan gasket. Matched with an unbent pan and pan leaks are a thing of the past.
That would be my path to resolution if I ever get a new pan. It is warped too much to straighten out and use a real gasket. Plus the mating surface is gauged in places from previous owner
 

Daveo91Burb

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Well it's kind of too late since I already bought a AC Delco gasket for $30+ but I haven't installed yet. I'm waiting for a NOS pan from eBay that I thought was supposed to arrive today. Are the lube lockers worth it over the OEM Delco? I googled and they look pretty good - I would have gone that way if I'd a known. I'm hoping that with new pan, no damage on tranny mounting surface, and new Delco gasket I can finally kick the leak. I'm going to give the pan's mounting surface (and maybe tranny as well?) a light coating of moly grease before I install.

Another annoyance.... my new custom y-pipe does not have enough clearance to install the pan with the filter installed. I had to remove the filter with the pan still under it to get the pan out. When I install I can either try to put the pan in place and then install filter OR I can lower the exhaust. That would suck since the PS manifold has headed bolts at the collector instead of studs and one of them is very hard to get to. I'm hoping I can wiggle on the filter with the pan in place.
 

Daveo91Burb

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New pan came yesterday, excited that it looks truly NOS, made in America. Seems like it was shrink wrapped and sat on a shelf since ‘95

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yevgenievich

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I can't take my pan off without removing the exhaust. Talk about annoying.(because I have higher capacity pan vs stock). I am still planning on ordering a new pan, but was going to go with aluminum version.
 

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I can't take my pan off without removing the exhaust. Talk about annoying.(because I have higher capacity pan vs stock). I am still planning on ordering a new pan, but was going to go with aluminum version.

Yeah I saw some of those in my search and was interested, but the price turned me off. Seems like at least $150? I think my plan for longevity is to use a torque wrench when I install the new steel one!
 

Daveo91Burb

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Got the new pan in today - looks nice and no leaks so far! did not have to lower the exhaust - was able to position the pan resting on the y-pipe and then maneuvered the filter in place and wiggled it up into the intake.
 

Daveo91Burb

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What the hell am I doing wrong? New oem pan and gasket and leaks like a sieve after it sits for a week. Torqued bolts in a staggered pattern in two increments - I think to around 12 or 15 ft-lbs. I put a light coating of grease on both the pan and tranny surfaces. Bad idea? Maybe acting as a conduit? Or do I have bigger problems?

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yevgenievich

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Half of my leak was from a trans connector running around the pan making it look more guilty. Not sure if grease on a gasket makes any difference
 

JoeR Jr

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You sure it's not coming from the shifter seal or someplace above the pan?
 

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Half of my leak was from a trans connector running around the pan making it look more guilty. Not sure if grease on a gasket makes any difference

Yeah, I'll take a better look this weekend. Both old pan and new pan, leak is in same place: back edge and PS towards the back. Doesn't seem like there's much above there to leak?
 

Daveo91Burb

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You sure it's not coming from the shifter seal or someplace above the pan?
Yeah, doesn't seem like there's much above there to leak, but I'm going to be looking a little deeper this weekend. Thanks.
 

yevgenievich

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Mine was leaking the most from the harness seal. Actually managed to replace the seal without dropping the pan.
 

Daveo91Burb

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Pretty sure the leak is coming from the dipstick seal. Felt around up there and it was very wet and I can see how it would drip off there and travel around the gasket, since that surface slopes down toward the back. And I had a hard time getting the dipstick tube in after I installed tranny - could have gotten damaged. Ordered new one just now - we'll see. Thanks for the advice.
 

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