Packard Forum Index » V-8 (1955-56)

Quote:

Never, ever use Permatex on any automatic transmission anywhere. It will come loose into the trans, start flowing around in there until it finds a hole that's smaller than it is, and plug it up. Then, you'll burn up the trans. Trust me on this, the only kind of sealant you want to use on any automatic transmission is shellac or something similar. Never use RTV.

Randy Thanks,
Thats great they are just up the road from me in Fredricksburg, Va. I'm in Williamsburg, Va area. I looked on their website and they have what I need.

Eric Thanks, Randy B. had a source for a new gasket. I have heard of using shelac as gaskets before but, I have never tried it.

Hi every one,Gary Russell of packard tips in #4 says to use RTV but to wait 48 hours before filling to let it cure.This guy must have been working on Packards for some time and he hasn't mentioned any failures.What gives.

Go to any reputable transmission shop and ask them about RTV. I don't know about everyone here, but if it costs $3000 to rebuild a trans, it's not worth the risk IMHO.

Ultramatic Dynamic recommends that the gasket go on dry. It will seal as the gasket absorbs a little tranny and swells.

Other than that I recommend just some spray-on copper gasket sealer.

It would seem reasonable to believe the best and first choice would be use the proper replacement gasket and follow the manufactures recommendations (if provided)or follow Packards service manual. If the gasket is not available then use shelac or equivalent.I agree after having thought about it for a couple of days, that RTV may be the least desirable. But the gaskets are available for $10.00 bucks + $2.00 S&H so I think that is the best choice.
Thanks for all of the input

Where a gasket was originally used, a gasket remains my first best choice.

Even if a gasket isn't available in ready-to-use form, I will cut my own. It's not that hard, and any parts store worth doing business with will have sheet stock available for that purpose. I've made hole punches out of scrap pipe and tube stock.

I have, however, applied a thin - almost transparent - coat of RTV to one side of a gasket to help with troublesome leaks, but only after checking and repairing the mating surfaces.

Others have reported using a thin coat of RTV to make for easy release (for pan removal).

Somewhere in this thread I saw what I thought was the belief by someone that shellac was a substitute for a gasket; not so. Under some conditions Permatex's "Form-a-Gasket" might do that, but shellac is just one of many types of gasket cements, like Permatex hardening and non-hardening varieties. On things like Ultramatic pans, engine oil pans, L-head valve covers, etc., I usually use shellac or the hardening variety of Permatex on the side to the pan, and nothing on the other side. Oft times removing things like valve covers later for a valve adjustment doesn't require a new gasket.

But one thing many people miss on stamped steel oil pans and automatic transmission pans is to correct the distortions in the steel that have been formed over the years by repetitive tightening of the bolts -- what then results is that you no longer have a flat surface to mate with the machined flat surface of the transmission or engine casting and the gasket may no longer be sufficient to make up for the differences. Lay the pan against some solid steel surface and using the rounded end of a ball pein hammer against the bolt hole, give a rap to flatten the stretched area around the bolt hole of the stamping.

As to the comments about no silicone on gasoline or automatic transmission pans, AMEN!

Quoth the Raven: "Never use any type of glue or RTV on the gasket or as a substitute for a gasket. Why? You may be asking...because if any of the dry rtv falls into the tranny it will clog it up, causing major tranny damage."

From: Muscular Mustangs