TR2/3/3A TR3A Rear Axle Pinion Oil Seal Replacement

[MGTF1250Dave]

Aloha All,

I'm getting ready to replace a leaking rear end pinion shaft oil seal in my '58 TR3A. I have a speedi-sleeve and new oil seal to fix the leak. Does any one have experience with this job? I'm wondering if I need to remove the drive shaft from the car in order to do the job. Is there sufficient room in the drive shaft tunnel to move it up or off to the side and get an impact wrench on the nut holding the pinion drive flange to the pinion shaft? Otherwise it seem it should be a fairly simple job. Thanks in advance.

 

[TR3driver]

IMO you'll have to drop the shaft to get in there with an impact wrench. However, I haven't tried it.

 

[martx-5]

If you have one of these impact universals you might be able to get away with it. If you lived a little closer, you could borrow mine.

 

[prb51]

Dave,
Yes the drive shaft has to be removed.
The pinion seal is in tight and difficult to remove as the pinion gear shaft projects thru the seal.
I drilled two small holes (dremel tool) into the brass seal body after putting grease around the drill point (to retain metal debris).
I threaded small screws into the holes and used a slap hammer to work the seal out, a little this side then the other.
Once out you can use the old seal (flatten the drilled screw holes first) to assist as a surface to push the new seal into place with a small piece of wood and a mallet. Fit new seal square and place old seal over it with wood driver and hammer gently side to side for an even fit.
Lube the new seal first and be careful not to mar the rubber seal lip when placing on the shaft.
I did this with a speedi sleeve too and not a leak in 3 years.

 

[MGTF1250Dave]

Thanks guys. Although not the answer I was hoping for, I figured the drive shaft would have to come out. I appreciate the confirmation.

 

[Geo Hahn]

I recently did this on a 59 TR3A and did not remove the drive shaft, plenty of room, just propped it up out of the way with a piece of 2x4 jammed under it.

Personally, I do not think you want to use an impact wrench. That nut is only on there with 100# or so (check the manual) which is easily freed with a standard breaker bar. More importantly, you want to preserve the pre-load and the simplest way to do this is to mark the nut and pinion and then count the number of turns you do to remove the nut. Won't be able to do that with an impact.

You then return the nut to it's prior position when putting it back together and Viola! you should have the same preload as before. Anyway, that's one theory.

For pulling the seal I used thia:

https://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=35556

...took about 3 seconds.

 

[prb51]

Geo,
When I use an impact wrench I do about what you mention and mark the nut and whatever is not moveable as ref. When you tighten with impact it sneaks up on the mark if you use low ft lbs. You can break it with a hand on and still count revs.
Misunderstood the question, duh, yeah push the DS out of the way.

 

[TR3driver]

The TR3 diff uses a spacer & shims, so you should be able to just torque the nut back to the specified 85-100 ft-lbs. The preload is set with shims, not torque.

And I agree that there is enough room to get in there with a socket & breaker bar without removing the driveshaft (as I have done that). Silly me, I was thinking there was some reason in particular you wanted to use an impact wrench ... I agree that it's probably not a good idea because the impact is going to be transferred to the gear teeth.

 

[MGTF1250Dave]

Thanks Geo & TR3driver, for letting me know that I shouldn't need to use an impact wrench to remove the nut. I was just assuming (my error) I would need one after my experience trying to remove the nut holding the output flange on the rear of the gear box. I wrestled with that for a couple of hour and decided I needed a break. I was tell my neighbor about my struggle and he lent me an electric impact wrench. After I ran the extension cord, the nut was loose in about 5 seconds.