Could use some suggestions - Have a trans pan leak - tried the cheap chrome pan route and gasket and it was leaking so I dropped a $100 on a PA aluminum pan - started it looked good - went for a drive and after parked found a small puddle. Tightened up a little more (over torque specs now) Same thing. Checked all the other areas (around tube, vacuum modulator, etc) and about 95% postive it's still the pan - any suggestions - this is the last leak I've got and it starting to become a mission.

 

first. You cant go over the torque specs. Once the pan is bent, you gotta make it unbent. It gets bent when you overtighten it.

System I use to not get pan leaks:

Clean pan with solvent or brake clean after removal.
If the gasket was folded inside a box as some of them come, flatten it out under some books or the pan itself overnight. If its in a fullsize package and isnt bent twisted or anything other than flat, carry on.
Next with the clean dry pan apply a 1/4" thick bead of Ultra Black RTV around the gasket seal area on the pan. Be sure to put the sealer on the inside of the bolt holes in the pan, and try not to get any in the holes themselves.
Only put RTV on the pan, not the transmission case. The pan is much easier to remove and clean, and also the pan is what leaks, not the case.
Place the gasket on the pan over the RTV after it has cured for about 2 minutes. Often the gasket will not want to stay aligned with the holes in the pan so I place bolts through the holes from the gasket side. If it is curling up somewhere you can use the bolts and something large and flat to hold it down.
If the bolt holes line up okay, just put the pan gasket side down on a clean workbench and let the weight of the pan hold the gasket on.Let it cure for another 2-5 minutes.
Make sure the case is clean and free of any oil on the gasket surface. Brake clean or a mild solvent on a rag usually will get the job done. Dont spray stuff into the transmission.
Now you can place the pan on the trans and put the bolts in. Just start them and give them a couple threads untill you have all of them in.
Using a socket on an extension with no ratchet, turn them into the trans case by hand. Leave them just finger tight untill all are holding the pan to the case.
Now with an inch pound torque wrench, tighten to spec in a cross radial pattern. Like putting on a wheel or bolting down a cylinder head.

If you still have a leak after that, it isnt the pan. The most overlooked leak area on an automatic transmission is the shifter quadrant. The seals will leak after years of neglect and repeated use, the fluid will drain down from the shifter and drip off the pan.

Other good things to change while you are under the car and have the trans apart. Vacuum modulator. May as well replace it. They have a lifespan and they are cheap. Drop the driveshaft and replace the rear seal on teh trans. Get the proper O rings and seal up the speedometer cable connection, its probably leaking too. Although if the speedo isnt leaking and its bone dry, dont mess with it.

 

Thanks alot for the right up. I probably did have some oil on the surface when putting gasket on. Did not think it would hurt hings. Did not use RTV either. Was not sure what you meant by "Be sure to put the sealer on the inside of the bolt holes in the pan, and try not to get any in the holes themselves".

Thanks again.

 

If your pan isn't bent, then you probably just need to use RTV goop to seal it. I prefer the Permatex "ultra black" myself.

 

While this is a GM pan, its still the same principle. Follow the path of the red line around the pan. There should be a raised area between the bolt holes, Put the RTV on top of that.

Go sparingly, you dont need so much goop on there it squeezes out and fills the pan, just a 1/4" bead is all that is needed. Unneeded glops of it can break off and clog the filter or get stuck in the pump and valve body. You dont want pieces of anything floating around inside a transmission, or an engine for that matter.

Ther Permatex Ultra Black is the best I have found for this stuff. Blue doesnt seem to work as well and Orange falls apart and leaks again after a while.

[IMG]local://upfiles/14646/2E06E1249358419FB963F28F8483F223.jpg[/IMG]

 

thnaks for all the tips - Just so i'm clear I have a cast alum pan from Performance Automatics - still need RTV?

 

Good cheap insurance..just use it sparingly..