RTV Sealant

[Ben99GT]

Found the Ford TSB...

TSB 05-10-1
LIMITED SLIP AXLE CHATTER, SHUDDER, BINDING
SENSATION, OR VIBRATION DURING LOW SPEED
TURNING MANEUVERS—VEHICLES BUILT BEFORE
4/1/2005

Issue: Some 2004-2005 Ranger vehicles may exhibit a chatter, shudder, binding sensation or a vibration during low speed turns. This may be due This may be due to the axle not having the proper amount of friction modifier installed.

SERVICE PROCEDURE
1. Raise and support the vehicle on a hoist.
2. Remove the differential housing cover bolts and drain the axle lubricant from the rear axlehousing.
3. Remove the differential housing cover.
4. Clean the mating surfaces of the rear axle and the differential housing cover.
5. Apply a continuous 1/8 - 3/16" (3-5 mm) bead of sealant to the differential housing cover.
• For 7.5 and 8.8 axles use Clear Silicone Rubber (TA-32)
• For 8.8 High Torque axle use Ultra Silicone (TA-29)
IF POSSIBLE, ALLOW 1 HOUR SEALANT CURE TIME BEFORE ADDING LUBRICANT.

You can run TA-32 in confidence, it sets up very quickly.

 

[OVERKILL]

But it would appear they RECOMMEND the TA-29........

 

[Ben99GT]

They recommend both, just for different applications.

 

[OVERKILL]

Originally Posted By: Ben99GT
They recommend both, just for different applications.


The "high torque" axle would be a more strenuous application from the sounds of things. There's no difference in the diff cover between the two 8.8's. An 8.8 is an 8.8. There are different styles of housings, but the covers are all interchangeable. It sounds like the grey is the recommended product for the more strenuous app, and thus, would be the "superior" product if one was given a choice between the two.

 

[Ben99GT]

The "high torque" 8.8 holds more fluid, but frankly, I'm not aware of the actual differences between the two axles.

What I can tell you is that I've been running clear RTV on the diff cover on my car for over 2 years, it makes 350+ rwhp, 350+ rwtq and has a TFS rear diff cover with bearing cap supports (more tension on the cover) and not an ounce of oil has weeped from the diff cover.

I've also seen clear RTV used on similar diff covers in 800+ rwhp apps with no problems either.

 

[OVERKILL]

And of course I've used the grey stuff on mine

I'm assuming yours is forced induction?

I'll be using the grey on my IRS diff. Just pulled the 3.27's out of it two days ago. 4.10's going in.

I'm not saying the clear junk won't work. I'm saying the grey stuff is a better product. A diff is pretty easy to seal compared to a lot of other applications.......

 

[bdcardinal]

im assuming the high torque implies that its the Torsen unit.

 

[OVERKILL]

Originally Posted By: bdcardinal
im assuming the high torque implies that its the Torsen unit.


Can't see it. There are a lot more "high torque" applications than the FX4 (which it's available in) such as the Terminator, Shelby....etc.

The traditional "T-Lok" clutch-pack diff setup is a lot more common.

They are all the same ring and pinion combo and can use the same carriers. The difference being the number of splines in the carrier.

I'm going to agree with Ben here, that it's likely the higher fluid capacity version (F-series) that makes it "high torque".

 

[Ben99GT]

Originally Posted By: OVERK1LL
And of course I've used the grey stuff on mine

I'm assuming yours is forced induction?


No, it's an n/a 4.6 4V.

Quote:
I'll be using the grey on my IRS diff. Just pulled the 3.27's out of it two days ago. 4.10's going in.

I'm not saying the clear junk won't work. I'm saying the grey stuff is a better product. A diff is pretty easy to seal compared to a lot of other applications.......


All I am saying is that if a quicker set-up time is important, use TA-32 because it seals a diff cover just as well as anything out there, and actually better than high-temp black.

I'm not denying that TA-29 is a much, much, much better adhesive and overall product, just that it's a bit "overkill"

for this application.

 

[eljefino]

Just thought I'd throw my hat in with the Permatex RTV from walmart is not the same as parts stores... it's worse. Goes on shiny while parts store goo goes on dull. Handling and setup go better and I have confidence in a better seal. The parts store stuff is slippery when you want slippery and tacky when you don't; WM the inverse. Will have to check the part #s but am betting they're different.

 

[OVERKILL]

Originally Posted By: Ben99GT
Originally Posted By: OVERK1LL
And of course I've used the grey stuff on mine

I'm assuming yours is forced induction?


No, it's an n/a 4.6 4V.

Quote:
I'll be using the grey on my IRS diff. Just pulled the 3.27's out of it two days ago. 4.10's going in.

I'm not saying the clear junk won't work. I'm saying the grey stuff is a better product. A diff is pretty easy to seal compared to a lot of other applications.......


All I am saying is that if a quicker set-up time is important, use TA-32 because it seals a diff cover just as well as anything out there, and actually better than high-temp black.

I'm not denying that TA-29 is a much, much, much better adhesive and overall product, just that it's a bit "overkill"

for this application.


Oh, now THAT is PIMP!!! Mark VIII swap or Cobra swap?

 

[Ben99GT]

Thanks...

It's a 2005 Lincoln Aviator long-block with mixed and matched Mach 1 and 99/01 Cobra parts (intake manifold/cams).

 

[OVERKILL]

NICE!!! I know another guy (local club) who picked up an Aviator longblock for the same purpose. That's awesome!!! Props for thinking outside the box!

That's the aluminum block right?

 

[Ben99GT]

Thanks again, yea it's an aluminum block. Long-block wise, the Aviators are identical to the automatic 03/04 Mach 1s and Merc Marauders, even down to the cams and valve springs. The Aviators just came with a variable runner manifold that has to go in the garbage.

 

[OVERKILL]

That's fantastic!

I bet it's surprised a few F-bodies

When you say variable manifold, do you mean like the IMRC stuff on the earlier Cobras?

 

[Ben99GT]

Originally Posted By: OVERK1LL
That's fantastic!

I bet it's surprised a few F-bodies

When you say variable manifold, do you mean like the IMRC stuff on the earlier Cobras?


It's surprised its share of F-Bodies, and even a GT500 or two.

The Aviator intake is setup more like the FR500 intake, with 8 internal butterflies (mounted at the entrance of the short runners) to control the long to short runner transition.

It's a really cool intake setup, but the runner shapes are terrible in them. No good for performance at all.

 

[OVERKILL]

Yeah, I could see that. Would work well for moving a rather heavy SUV though.

Got any pics?

 

[Ben99GT]

Yea, the long runners are looooong with a really narrow cross section. Short runners are only about 9" though, but the transitions are so bad it kills them.

I deleted the runner control butterflies, but you can see the holes where the rod ran through (in the entrance of the short runners 3rd pic).


Runner control motor :
Down the short runner:
Massive injector bumps:

 

[c3po]

I dumped the fluid that had Auto-Rx in it, and I put the RTV on and used a lamp for a while. I am not to concerned with it drying since when I add the diff fluid it will be 120 hours later.

 

[OVERKILL]

Originally Posted By: Ben99GT
Yea, the long runners are looooong with a really narrow cross section. Short runners are only about 9" though, but the transitions are so bad it kills them.

I deleted the runner control butterflies, but you can see the holes where the rod ran through (in the entrance of the short runners 3rd pic).


Runner control motor :
Down the short runner:
Massive injector bumps:




Ahhh yes, that's completely different from the IMRC stuff on the older Cobras.

Have any pics of your car?