I bought a Mr. Gasket Chrome Transmission Pan an its to narrow. (TH 400) I was hoping maybe someone of this site could recommend another company to buy from. The old pan just keeps leaking no matter what is done to it. So I thought a new one might work better.

Any idea where it is leaking? Perhaps its not the pan gasket, but a shifter seal or tailshaft seal.

If you feel pretty confident it is the pan causing the leak, I recommend a cast aluminum pan. It has substantial material to mate with the bottom of the transmission and will give you a good seal.

As far as a source - I am not sure, but I would check with one of the many Pontiac engine building companies.

Tom

I had the old original pan on mine , pretty dinged up and leaked ,I could never get it really straight along the edges...
I bought a TCI cast aluminum pan from Summit, it holds 2 more qts also and has cooling fins, had to cut less than 1/8" off the frame flange to get it in ,but well worth it ...its $115 for 400, for my th350 it was $104

and has drain plug

Look here....
Tranny pans from Jegs

Kel

From just about everyone I've hear of buying a "chrome" oil pan or tranny pan... they have nothing but problems.

I've hear nothing but good things about the Aluminum pans (as long as it's a quality one) And if your going to get a new pan, get one with a draim plug if you can. You could at least change or inspect the fluid when needed with out dropping the pan (other than a filter change)

As Kel pointed out, Jeg, Summit etc have a good selection usually.

Good luck, and let us know what you get?

Brett - 67 Drop Top 455! (TH400)

I got mine from Classic Industries, although I have not mounted it yet.

B&M also sells aluminum pans.

- Jake

You can be pretty sure that the chrome plated stuff will not seal. I just put a cheap polished aluminum I picked up off ebay for $35 and it looks great and no leaks.

The big probem with leaking pans is that the bolts are too tight and/or not torqued correctly. If you want to take anothe stab the the origional pan, remove it and super clean the mating surfaces. Look closely at the holes in the flange, and you will probally notice that they are distorted.

Tap the distorted area so that it it's flush or even a little concave on the mating surface. Use a cork gasket without sealer, and start all bolts finger tight. (If you have trouble keeping the gasket in place, a couple dabs of spray adhesive or grease on the gasket will hold it in place.) Do not start tightening on the corners of the pan because those are the last ones you want to tighten. Start tightening in the middle of the straigh areas of the flange and stagger each side of the pan. TIGHT IS A HAIR MORE THAN FINGER TIGHT. Get them just snug, run it to get it hot, then snug them again.

I've tried and tried to get my steel pan to seal. I've tried both rubber and cork with and without sealer. I also recenly replaced the front and rear seals, seal around the shift selector, o-ring on the dipstick tube, speedo gear housing gasket, and the tail shaft housing gasket. In the process I also checked the pan with a straight edge and dimpled the holes....then torqued to 12 ft lbs. I'll be damned if it's not leaking around the pan AGAIN! At this point I could've already put an aluminum pan on it and been done with it! Yes, I have verified the fluid is not comming from anywhere else....it's definitely pan gasket related. Time to put on a new pan.....gives me a reason to get the car off the ground and redo the exhaust, too.

Drew