ZF advice/help please

[Kizer]

I’m on round 3 of output shaft seal (rear seal) replacement.

I broke the trans, replaced it with rebuilt transmission…seal leaked and I ASSumed that the seal leaked because I had stored the trans dry for a few years.

Replaced the seal…still leaks…read the service manual. Assumed, again, that the new seal leaked because I’m certain that I didn’t get 200 ft lbs of torque on the yoke nut.

Replaced again and leak is worse! I know that I got 200 on the nut.

I don’t understand what I’m missing. Any help will be greatly appreciated.

Kizer

 

[u2slow]

How are you sealing the spline? Is the yoke body smooth without any wear grooves? Is there play in the output bearing?

 

[hacked89]

This reminds me of my experience with CAD seals on dodge axles

 

[Kizer]

How are you sealing the spline? Is the yoke body smooth without any wear grooves? Is there play in the output bearing?

I’m using thread sealer on the splines.

The yoke doesn’t appear to be damaged and the trans that I broke received it with no leak.

The output shaft doesn’t deflect and no vibration when driving.

 

[Kizer]

This reminds me of my experience with CAD seals on dodge axles

You said the “D Word”!

 

[u2slow]

Thread sealer? Is it working, or that the leak source?

My dodge transmission specifies anaerobic sealant (similar to loctite) on the spline, and on diffs I typically use ultra-black rtv on the pinion spline.

 

[Kizer]

Thread sealer? Is it working, or that the leak source?

My dodge transmission specifies anaerobic sealant (similar to loctite) on the spline, and on diffs I typically use ultra-black rtv on the pinion spline.

I’m using the Loctite brand thread sealer (white tube).

It looks like the seal is leaking around the outside of the inner part…if that makes sense. I’ve been using National (brand) for the seal.

 

[u2slow]

Wrong sealant... That will have Teflon in it for making threaded pipe joints seal. Doesn't really set up. I use permatex anaerobic flange sealant part # 51531.

I usually put a small smear of rtv on a seal before tapping in into the housing.

 

[Kizer]

Wrong sealant... That will have Teflon in it for making threaded pipe joints seal. Doesn't really set up. I use permatex anaerobic flange sealant part # 51531.

I usually put a small smear of rtv on a seal before tapping in into the housing.

10-4
I’ll give it a run.

Is it possible that I’m seating the seal too far back…or not far enough?
The seal wants to stop about 3/16 beyond flush with the tail housing (inside).

Thank you.

 

[Jesus Freak]

It should stop at the right spot.

 

[u2slow]

The exact depth shouldnt matter so long as it seals on the ID and OD.

 

[IDIBRONCO]

I use permatex anaerobic flange sealant part # 51531.

I usually put a small smear of rtv on a seal before tapping in into the housing.

I think that these two should get your leak stopped. The anaerobic sealer is very important.

 

[Kizer]

Quick update: Work (for $) happened.

I hope to get the seal in Sunday.

I’ll update with results.

 

[Jesus Freak]

Other than the fact that time is harder to come by than $, it is nice when $ opportunities show up. Then when time opportunities finally show up.......... you ain't got no $$$! What's up with that?

 

[bulletpruf]

Quick update: Work (for $) happened.

I hope to get the seal in Sunday.

I’ll update with results.

Please let us know what happens; I'm in the middle of a ZF-5 rebuild right now.