Best Transmission Gasket - Or are they all equal

[70cst]

I need to replace my gasket on my transmission pan ... is there a preference to a specific gasket or are the all the same. Thanks

[MARKDTN]

I like the genuine GM ones. Part of the reason is that they ship flat, not folded.

[n33k0]

I bought a gasket and filter kit from my local autoparts store for my TH350 and haven't had any issues with it. Sold under the brand name "TCI Auto", made out of a rubber material, no issues fitting on the pan, no need for additional sealant. Like MARKDTN mentioned, it did come folded up in the packaging, and would not lay flat on its own, but it didn't cause any issues once mounted and sandwiched in place.

[Jrainman]

I don't know if any one is better then the others I have used them all , I will say stock pans are thin and can get out of shape by overly tight bolts, so check your pan around the bolt hole areas when you pull it ,make sure they are flat and not pulled in. and all gasket surface is flat.

make sure surfaces are 100% clean and dry , some guy add a tack spray to help them make the install easier ,some don't everyone has there own way .

Also use a 1/4'' socket rather a 3/8 this will help you get the lite torque spec with out over tightening the bolts . this is the most important part... over tight the bolts and you will be back to square one.... (leak)

[70cst]

Thanks

[leftybass209]

I purchased two rubber cheapie gaskets for my 700r4, and not a drop spilt.

Transmission shop did some work and used a "premium gasket" and the damn thing leaks front to back.

Go figure.

[DT1]

Originally Posted by leftybass209

I purchased two rubber cheapie gaskets for my 700r4, and not a drop spilt.

Transmission shop did some work and used a "premium gasket" and the damn thing leaks front to back.

Go figure.

I've been plagued by transmission pan leaks. Tried flattening out the pan and almost every brand of gasket/sealer but always, after a few weeks-still leaks.
A while back I picked up an aluminum pan and a nice thick MrGasket pan gasket. I applied a thin coat of RTV and slapped it on. After more than a year, still no leaks.

[n33k0]

Originally Posted by leftybass209

I purchased two rubber cheapie gaskets for my 700r4, and not a drop spilt.

Transmission shop did some work and used a "premium gasket" and the damn thing leaks front to back.

Go figure.

Some shops only have one torq spec that they apply to every nut and bolt, "impact wrench".

[Jrainman]

Originally Posted by DT1

I've been plagued by transmission pan leaks. Tried flattening out the pan and almost every brand of gasket/sealer but always, after a few weeks-still leaks.
A while back I picked up an aluminum pan and a nice thick MrGasket pan gasket. I applied a thin coat of RTV and slapped it on. After more than a year, still no leaks.

I agree with this route you took, the pans get old and weak in the bolt hole area and you can flatten them out but you really never get them perfect , the aluminum pan is much thicker that will provide a thicker seal.

But you have to watch out on some aftermarket Pans , some times the cable brackets may need to be altered to get them to fit properly . it not a big deal but just letting you know what to expect and look for ,as far as compatibility .

[cleszkie]

I have good luck eliminating leaks by using a very little bit of teflon thread sealant paste on the pan bolts. I noticed that my leaks were caused by ATF making its way past the bolt threads, and this entirely stopped the leaks.

[DT1]

Originally Posted by cleszkie

I have good luck eliminating leaks by using a very little bit of teflon thread sealant paste on the pan bolts. I noticed that my leaks were caused by ATF making its way past the bolt threads, and this entirely stopped the leaks.

Something I never thought of. Makes complete sense.

[RedRoad]

Ive been chasing leaks on a rebuilt 350 since I got it from the shop. I ended up using Milodon reusable gaskets (blue rubber with steel core) and it finally stopped the pan leak on the new B&M cast aluminum I put on. Now its just leaking from the linkage shaft as it goes into the case, did I mention I HATE auto transmissions!!!

[70cst]

Thanks All Appreciated

[wolfsmurf70]

old mechanics trick is to tie the gasket to the corners of the pan with thread or fishing line before installation so as not to chance getting rtv into the pan. works like a champ every time I use it. as for the leaking after a while I have seen gaskets settle for lack of a better term and need to be tightened another half turn or so after a few hot/cold cycles.

[50bomb]

I thought I was the only one that had this problem. I just recently put a new gasket on my th350. Always fixed the problem on my other vehicles but this time it still leaked. I bought the one mention from napa that is folded in the box that is all they carried. I had to put alil rtv to hold it in place. Tighten the bolts down like I have always done and NOpe it leaks still and worse then it was before. Daily driver problems And I have to drive daily driver 64 c10 this Sunday 70 miles to my new place. Hope it makes it without blowing something. I never drive it that far. did i mention I have a leak on the back of the motor oil pan gasket too? BLAH Leaks are my worst enemy besides rust/rot/bondo/everything in between haha. Gotta love these oldies though.

[leftybass209]

Since this thread was brought back to the top, I will add some info again. The brand of gasket the Trans shop used is called Farpak. Didn't work for me, leaked everywhere, front to back, side to side. Actually, the bolts were NOT overtorqued as I had previously thought, I checked them with a torque wrench to be sure, the gasket just sucked.

I replaced with yet another sweet O'reilly powertorque gasket, or something like that and again, no leaks.

I don't use tricks, gimmicks, wives' tale sure fixes or anything of that nature, on ANY gasket. I install whatever I get according to the way the manufacturer of the gasket suggests. For underside pans, I use the felpro snap-ups to hold the gasket and pan to make life easier, and help me swear a lot less. The only thing I've ever done that would be considered different, is replaced front and back manifold gaskets with a bead of RTV, which has seemed to work well.

[trac209]

I use the plain cork ones with a spray of copper gasket spray

[70cst]

Thanks for the info ...