[elimin8r]

Can fluid leak out thru the treads on the pinion nut or even somehow thru the splines of the yoke? 8 inch in a 67.

 

[towcat]

Anything is possible, but I have never seen that happen, have you checked the pinion seal, that is most likely the problem.

 

[1969XR7Vert]

I have found junk in the hole the pinion nut sits in and when I assemble a rear I make sure to use some ultra black RTV on the pinion threads/pinion nut to avoid this problem. Thinking about how the rear goes together it is entirely possible to have oil get up through the splines and out into the pocket if sealer is not used.

 

[elimin8r]

I have found junk in the hole the pinion nut sits in and when I assemble a rear I make sure to use some ultra black RTV on the pinion threads/pinion nut to avoid this problem. Thinking about how the rear goes together it is entirely possible to have oil get up through the splines and out into the pocket if sealer is not used.

I did some research and found out when you rebuild your diff. you should use RTV on the splines and threads just for some insurance. So yes i guess it can.

 

[towcat]

I did some research and found out when you rebuild your diff. you should use RTV on the splines and threads just for some insurance. So yes i guess it can.

Where did you find this information, I would be interested to read it.

 

[elimin8r]

Google. Type in 8 inch pinion leak. This is one site.
http://www.clubhotrod.com/hot-rod-talk/49324-8-ford-diff-leaking-around-pinion-nut.html
Lots more to read in the search.

 

[1969XR7Vert]

Carlton and I had some discussion about this via PM and it went something along the lines of Carlton saying the shop manuals and such do not say anything about needing to seal the pinion/yoke splines and nut (which seemed "good enough for me") and I described how it is all metal to metal sealing for oil to find it's way out to the splines/nut and it seemed conceivable (to me at least) that it was possible to get a leak in this manner (and thus why I use RTV as an extra measure).

The forum link posted seems to support what I conceive as possible. Seems to me that if you find gear lube in the pocket, then you have such a leak. It seems unlikely that oil leaking from the seal area would find its way into the pocket, it would be thrown outward.

 

[towcat]

I guess I am just hard headed, but if oil leaks out the splines, then something is worn to let this happen. If using RTV cures your problem, then by all means use it, I have never had to, and I have been through a lot of builds. When you remove the pinion nut most builders use a new one, and they come with a thread locker already on them.

 

[1969XR7Vert]

I guess I am just hard headed, but if oil leaks out the splines, then something is worn to let this happen. If using RTV cures your problem, then by all means use it, I have never had to, and I have been through a lot of builds. When you remove the pinion nut most builders use a new one, and they come with a thread locker already on them.

Carlton,

Nothing wrong with being "hard headed" in my book, especially when it leads to good dialogue such as in this thread. When it doesn't (i.e. I'm right, you're wrong) that's not always so great but it happens. In short, it's all good!

Regards,

Bob

 

[elimin8r]

I tend to believe somthing is worn also. But will give the RTV a try. Don't want to spend money on a new yoke and pinion if a little sealer works.