Gasket or RTV?

Beerj · Sep 22, 2019

Got my trans from PTC and the pan leaked right away. Found a hunk of oily dirt between the trans and gasket, no big deal, **** happens. I didn't have a gasket on hand so laid down a bead of rtv. Reassembled and still leaked at the pan. Pulled it again and went with a moroso gasket since I had good luck with them before. Torqued to spec and it leaked again. Said screw it and snugged them up real good which slowed it but still dripped a little. I just installed my temp sender in the pan and would like to seal it up so it's, well, sealed for the last time. What's the general consensus here? Gasket or rtv? Both surfaces are perfectly clean and wiped down with acetone as they were on the previous attempts. Also, closely inspected the trans and pan. No cracks, gouges etc and they appear to be perfectly flat as far as I can tell.

kmcminn · Sep 22, 2019

I cant get a trans pan not to leak. Seems the more I drive it the less it leaks. I have used every type of gasket. From cheap to lube locker. Torque in sequence even use a torque wrench to get the correct lbs. On this trans I have a lube locker gasket and a 150$ tci trans pan, sob still leaks.

Good luck

Beerj · Sep 22, 2019

kmcminn said:
I cant get a trans pan not to leak. Seems the more I drive it the less it leaks. I have used every type of gasket. From cheap to lube locker. Torque in sequence even use a torque wrench to get the correct lbs. On this trans I have a lube locker gasket and a 150$ tci trans pan, sob still leaks.

Good luck

I'm half tempted to pull the moroso gasket off of my old trans and see if it works. Maybe slather both sides in rtv while I'm at it. Honestly, it wouldn't be so bad except turbo 400's have their full mark at pretty much exactly the top of the pan. Then when you shut down, the fluid drains into the pan which puts the level above the gasket. Mine usually leaks when it's parked, hardly at all when I'm driving.

kmcminn · Sep 22, 2019

Leaks drive me crazy. I have fought these for years. Now I just buy absorbant pads and stick them on top of the skid plate while its sitting in the garage.

Beerj · Sep 22, 2019

kmcminn said:
Leaks drive me crazy. I have fought these for years. Now I just buy absorbant pads and stick them on top of the skid plate while its sitting in the garage.

I've been using pads too. Luckily, my drips miss the pan and go straight to the floor. No leaks if I backed into the garage since it's uphill to the door and my leak was at the front of the pan.

kmcminn · Sep 22, 2019

Beerj said:
I've been using pads too. Luckily, my drips miss the pan and go straight to the floor. No leaks if I backed into the garage since it's uphill to the door and my leak was at the front of the pan.

I guess we don't have to check levels as long as we got drips.

617_Racing · Sep 22, 2019

What pan is it?
I always had trouble getting stock pans to seal.

1tonyj · Sep 22, 2019

617_Racing said:
What pan is it?
I always had trouble getting stock pans to seal.

I had to go to a lube locker gasket to keep mine from leaking. I'm running a ribbed aluminum pan

leeman1790 · Sep 23, 2019

Do you let the rtv skin over before you put the pan on and torque it?

leeman1790 · Sep 23, 2019

Also, I had a th350 pan that leaked foreverrrrr and I finally figured out it was the shift shaft seal on the left side that let fluid leak down and soak around the pan. That was a tricky one

Beerj · Sep 23, 2019

617_Racing said:
What pan is it?
I always had trouble getting stock pans to seal.

Deep cast aluminum pan. No idea who makes it. Whatever ptc puts on theirs.

Beerj · Sep 23, 2019

1tonyj said:
I had to go to a lube locker gasket to keep mine from leaking. I'm running a ribbed aluminum pan

I'm definitely not opposed to trying one.

Beerj · Sep 23, 2019

leeman1790 said:
Do you let the rtv skin over before you put the pan on and torque it?

I didn't let it skin over but I know what you mean. I go finger tight with the bolts and let it sit for an hour and then torque evenly. Cure for a day before filling. I was expecting to find a leak somewhere else since I fought the pan so long but everything above looks good. Even used rtv on the dipstick tube when I first installed since they like to leak out of there too if the orings aren't perfect.

Just googling around, lots of people say to rtv a gasket to the pan and then bolt it up. Last time it was leaking between the trans and gasket so I don't think it would necessarily work in my case.

onetoncrawler · Sep 23, 2019

I've always used the HD Aluminum pans that PTC sells with the factory style cork gaskets and never had an issue?

Beerj · Sep 23, 2019

onetoncrawler said:
I've always used the HD Aluminum pans that PTC sells with the factory style cork gaskets and never had an issue?

The one that came on it was a black rubber gasket but I didn't trust trying to reuse it due to the indentation left by whatever was stuck between there. It's just a little depressing because my $110 junkyard trans never leaked, yet the new one never hasn't leaked. If it leaks again I might just take it to a shop for a "guaranteed fix" and let them fight it. That or just deal with drips and never have to change the fluid.

extremetownie · Sep 23, 2019

I installed a check valve in my return line. That way the oil from the cooler does not flood the pan. Stopped my leak.

Sawzall · Sep 23, 2019

I use a very light coat of Ultra Black wiped on both sides of the gasket from the bolt holes to the inside of the pan only. That gives the outside of the gasket surface to grip and not push out. I make sure my steel pans are straight and don't over tighten. Never have any leaks.

BUG-E J · Sep 23, 2019

leeman1790 said:
Also, I had a th350 pan that leaked foreverrrrr and I finally figured out it was the shift shaft seal on the left side that let fluid leak down and soak around the pan. That was a tricky one

I had the same thing happen to me. Those are kind of a bitch depending on how much room you have.
I use the gasket and rtv on everything I can. Gray ftw

Beerj · Sep 23, 2019

extremetownie said:
I installed a check valve in my return line. That way the oil from the cooler does not flood the pan. Stopped my leak.

I'd have to get creative to add a check valve since my lines run out the side of the cooler.

Beerj · Sep 23, 2019

Sawzall said:
I use a very light coat of Ultra Black wiped on both sides of the gasket from the bolt holes to the inside of the pan only. That gives the outside of the gasket surface to grip and not push out. I make sure my steel pans are straight and don't over tighten. Never have any leaks.

Kinda what I was thinking. Tried each one separately so now time to do both.