Small leak from rear transmission

[rjinga]

Disclaimer - I'm not a mechanic, and I did do a thread search AND check the TM manuel before posting.

I've got a small leak coming from my rear differential. It appears to be coming out of where the U joints meet the differential? (see circle in photo)

I have been in the water lately. No more than a few minutes at most (got temporarily stuck), but the differential was probably submerged. I noticed a "wet spot" the morning after being in the water. It was a bigger leak/spot that day than today.

Possible causes and solutions?

 

[gvaneck]

Its probably your pinion seal and btw its your rear differential

 

[rjinga]

Its probably your pinion seal....l

Ok, let's assume that it is the pinion seal. Is that something a rank amateur wanna-be mechanic can replace?

 

[kipman]

Yup, easy fix. a impact will help removing the pinion nut.

 

[rjinga]

Is the pinion seal replacement in the TM 9-2320-289-20? I can't/haven't find/found it.

 

[Cucvnut]

just dont mess up the crush sleeve.!

 

[ODdave]

Yup, easy fix. a impact will help removing the pinion nut.

Dont throw caution to the wind though, you do need to know what your doing. The pinion nut needs to be re-installed to the EXACT same tourque that it was proir to removing. to loose and the pinion can "walk" in & out causing gear wear & noise, posibly spin a bearing on the pinion. To tight and there will be excesive gear wear & heat on the bearings causing them to burn up.

"technicaly" you should repace the crush sleave.

I am not trying to scare or deture you from doing the job, just read up and make shure you do it correctly.

 

[bguy193]

You will have to pull the pinion to replace the crush sleave. If you do not replace the pinion bearings you will need to have 10-15 in lbs of rotating torque and 20-25 in lbs for new bearings. Some people that do not want to tear down the rear end mark the pinion nut in relation to the pinion and count the threads to reseat the nut in the same position.......But I do not recommend it. Once the crush sleeves tension between the bearings is released it cannot hold the propper tension again causing improper pinion depth leading to ring gear damage. My advice would be to get a book on rear ends and study, or take it in to a shop It's really not that bad of a job it just takes time and sometimes a little swearing. It is also a good idea to buy a couple of sleeves in case you overtighten the first one, because then you have to start over.
Good luck and happy trucking

 

[ODdave]

good time to do a solid spacer!

 

[rjinga]

Oooook, sounds like I'm on my way to my friendly neighborhood (real) mechanic. Thanks for all the info guys.

 

[rjinga]

Well, I got her back from the mechanic today and I did have a leaking pinion seal, AND water in the rear differential. (I've got to stop listening to my 14 yo son - "I think we can make it through Dad!" We didn't; but, after a few minutes of submerged forwards and backwards straining, we were able to back out)

I think we need to start a new thread - What have you PAID to have done to your CUCV lately? I'll start it off: replaced rear pinion seal; drain, dry, refill rear differential; new oil and filter; new fuel filter; top off coolant; check all fluids; lube. It's only money, right?

 

[Oldsouthernboy]

A rebuilt transmission, refurbish transfer case, total front end rebuild, #1 alt rebuild, and a whole bag of new lanuage that will make most people blush.

 

[bguy193]

a whole bag of new language that will make most people blush.