Differential oil seals

Hello again,

I keep digging a bigger hole for this car. I might get it on the road this summer. 1972 TR6. I removed the rear differential hoping to just replace the mounts but as suspected the R/H fwd mount is cracked. I ordered the repair kit from TRF. Anyone repaired these with out removing the body?

The differential took about 4 hour to clean up, 35 years a dirt and oil. during the clean up I emptied the diff and there was only about a cup of oil in it. I removed the rear cover and every thing looks good. I ordered seals for the pinion and the inner axle. Here's the problem. I read in the MOSS Part catalog that anytime the pinion nut is removed you have to replace the collapsible spacer if installed. The diff number is CD35417 would indicate that it has the solid spacer. If correct would it be ok to just replace the seal and retorque the pinion nut? Any thoughts on the subject. I checked the Bentley manual and it did not mention this.

Steven

Steve,
I used TRF reinforcements on the forward mounts with body on. I didn't do the welding, but it was tedious because it's all overhead - get the car up as high as possible. And wrap the gas line from the tank.

Be sure to prefit - I had to do some grinding to get them to fit really close. There's a large washer for the upper end of the pin. Since you can't get to the top side of the frame, I cut it in half and welded it to the pin at the underside of the frame. That was 3 years ago and so far so good.

Jeff
74 TR6 CF13816U

Jeff:

The earlier cars did not use the collapsable spacer, my 250 didn't, but I don't know when they switched over. As for the stub axle seals, thats a machine shop job, you'll never get the stubs out without a press.

Also, I'm not possitive but I thought only the trannny had brass/bronze components that could not handle the GL5 oil.

I just bought 2 quarts of GL4 based hypoid at Napa, they did have to order it for me though.

Someone please chime in if I am mistaken on the GL4 vs GL5 in the diff.

gjh said:

Jeff:
Someone please chime in if I am mistaken on the GL4 vs GL5 in the diff.

Click to expand...

John Esposito at Quantum Mechanics reccomended I use GL4 in my newly rebuilt diff. Apparently GL5 will eat through the brass shims inside the diff.

Rob.

I used the gear oil from TRF for that exact reason.

Pictures of seal installations done on mine are here:

https://www.74tr6.com/differential.htm

Steven_B said:

I read in the MOSS Part catalog that anytime the pinion nut is removed you have to replace the collapsible spacer if installed. The diff number is CD35417 would indicate that it has the solid spacer. If correct would it be ok to just replace the seal and retorque the pinion nut?

Click to expand...

Sounds like you do not have a collapsible spacer. If you did have, then the way to get that back together without having to install a new spacer is to carefully count the number of turns that it took to remove the pinion nut, and then reassemble to that specific number of turns, regardless of torque spec.

If you have a solid spacer, then you should have pinion spacer(s) already installed to set the pinion bearing pre-load. As long as you have not taken the pinion drive and bearing apart, then re-torquing the pinion nut to spec should give you the same bearing pre-load that you had before (for better or worse). If you have not taken the pinion nut off yet, I would could the turns anyway, just as a second-check for when you re-assemble.

After assembly you can check bearing pre-load with an inch-pound dial gauge. Pre-load spec on a Spitfire is 15-18 inch-pounds, should be the same on a TR. Differential pre-loads are usually in the 15-25 in-Lb range, so if you're not sure, around 18 in-Lbs should be good.

Replacing the pinion seal is pretty simple. Replacing the inner axle seals is easy too, except for getting the bearings off, for which you will need a press. Also, make sure you do not destroy the steel circlips that hold the axle bearings in place on the shaft. I just yanked them off, assuming I could just install new circlips. Wrong. Turns out these are pretty hard to find. I got some from Chris Hollum in Beaconsfield, but they were the last he had, and they were expensive.

As per other posts, I would use GL-4 gear oil when you refill. You can get GL-4 in Canada, but you may need to look around a bit for it. Most of the specialty auto parts retailers can get it for you. Canadian Tire or Napa do not stock it (at least in Ontario). I use Pennzoil #56076, a synthetic GL-4, which I got from Benson Autoparts.

Thanks Ross,

I will try tonight to see with a mirror what is inside. I have already removed the pinion nut. I have access to a press for the inner axle. Thanks for the info.

Steven

If you use a press for the inner axles, let the press do the work. Line it up and put just enough pressure on it to hold it in place, cover it up with towel, put a box with some kind of padding under the press. Then put it under load, and walk away. It might take 10 mins or so but it should pop out on its own.

I really do not recommend standing over it and increasing the pressure until it pops. It is a good way to get hurt.

RobT said:

gjh said:

Jeff:
Someone please chime in if I am mistaken on the GL4 vs GL5 in the diff.

Click to expand...

John Esposito at Quantum Mechanics reccomended I use GL4 in my newly rebuilt diff. Apparently GL5 will eat through the brass shims inside the diff.

Rob.

Click to expand...

That information is really about 10 years out of date. MODERN GL5 lubes use a much different formulation than the earlier GL5's. The earlier lubes had free sulfur atoms. Modern GL5s have sulfur compounds which don't react with yellow metals. Likewise, the concentration of chlorine compounds have been reduced. For a change, we can thank the environmental regs. Because GL5s are better under the types of pressure / sliding action in a diff, it is probably the better choice in the diff. (As long as you stick to a reputable brand)
However, it is probably best to avoid GL5 in the transmission since the EP additives tend to interfere with proper operation of the syncros.
Yisrael