Fla96LT4

What type of sealant do you use on the carrier bolts at the diff and trans? Thanks :confused:

6spd89

I need to know this too!!I was just getting ready to post the same ????'s.
Just polished my driveshaft(mothers) and installed my new seal at the
rear of the tranny.I'm ready to finish up but I have to go eat turkey,OH well!!
Tomorrow,tomorrow--------
Matt

vettenuts

If your cars are like mine, the original material was white and was somewhat brittle. GM changed the part number several times over the years. I bought mine a year or so ago. Lo and behold, when you open the GM box here is what you actually get:

Rapid Cure Auto Glass Urethane Adhesive, U-400

Made by Essex Specialty Products, Inc.
1250 Harmon Road
Auburn Hills, MI
248-391-6300

So, if you get a urethane caulk for installing a windshield it should work and you may save a few bucks in the process.

Rich B.

I've only taken a quick look at mine, but...

...Why do you need to seal them??? Mine don't seem to go through the unit itself (innards, I mean), so why seal them???

Why not just neverseize them??? :confused:

vettenuts

It is not a matter of "sealing". I spoke with GM Corvette Engineering about this. The sealer is added to prevent electrolysis of the different metals. Not sure I fully agree with explanation, I tend to think noise was also an issue.

Rich B.

OK; that makes sense. When steel & aluminum are placed together, and there is liquid present, you get a galvanic reaction.

Up here in salt-on-the-roads land, it's 10 times worse...

I use Neverseize, but if GM recommends a sealant, then they know best... :chevy

Fla96LT4

The old sealer was light colored and brittle. Sort of looked like hard window caulking.
I did not think about the different metal issue? The shop manual says seal around the C beam and at the points where bolts go through the trans and differential. I though it was a noise issue, as the fit is loose where the bolts go through the members? Or to add some stability to the parts moving? How does applying a surface sealer stop the reaction when the metals still touch? :confused:

Romeo Barrera

I just used black RTV on the mounting surfaces. I believe I heard that you need it to take up the slack between them, which reduces vibration.

AquaMetallic94LT1

I used black RTV also. The sealer is supposed to keep moisture out of the contact surfaces. :cheers:

mash557

Different metals????The only steel involved is in the bolts. Tranny housing, rear axle housing (Dana36) and C-beam are all aluminum. I fully agree on the noise issue as their is quite a bit of stress on that beam.

vettenuts

Check a steel bolt in an aluminum boat that has been in salt water. Nasty!!! :eek:

GRX

This is more critical where the roads are salted in the winter. The reason is electrolysis between different metals and or the presence of brine. RTV (silicone) sealant is fine. Use liberally to keep water away from bolt threads and mating aluminum surfaces. Don't forget the ANTI-SEIZE on the bolt threads. :chevy

Jim-K

I have my trans out now. I suppose the sealant provides two purposes, to cushion the load, and to prevent corrosion. It seems like candle wax would keep the water out, but would not stand up to the banging around the torque arm must go thru. If the bolts really needed to be isolated, then nylon shims could be used, but no relief is put in there for that.

Besides, most of our vettes are kept in the garage, and prolly not driven in the rain at all, and you really have to keep dissimalar metals submerged 100% to get any significant corrosion. If that was the case we'd have zincs bolted on the differential :crazy: My torque arm had no sealant at all when i pulled it apart, and theres no corrosion. Although I'm not so sure it was as rigid as it should be.

The other extreme would be 3M 5200. That would make that torque arm solid, but geeezz i feel sorry for anyone trying to get that torque arm back out if it was glued in with 5200... :smash: With that stuff you might not even need the bolts :p: Black RTV sounds like a good idea, although i'd like to use something a bit tougher. The flip side is, the tougher stuff you use, the harder it will be to get back out.

I'm still undecided...

Jim-K

vettenuts

Well, based on my experience, if I were to go with an over the counter product I would use Permatex "Right Stuff". It has a similar consistancy as that which the GM part has and I have used both.