TR2/3/3A Differential removal

[Talon]

Okay, I've pulled out the left rear axle on the TR3A and will now tackle the right. After that, I need to examine the gears in the center case for damage.

Question 1: How necessary is it to use the special case-spreader tool that the manual suggests is indispensable. I have no machining equipment (or expertise) to make such a tool myself, and don't want to buy things that I will only use once or twice, if it can be avoided.

Question 2: Once I get in there, how necessary are the special pulling and pressing tools on the seals and bearings and such?

Question 3: The manuals are not totally clear to me on the question of whether I should (or must) pull out the differential casing and then open and work on it without getting neck strain under the car. The manuals seem to assume that the whole thing will be removed, and it may become obvious (or unavoidable) once I'm in there and disconnect the drive shaft. Obviously, it will be a lot easier to work on if removed, but I don't want to invite other problems if removal is going to cause a chain reaction of issues.

Question 4: I assume that Moss Motors, my usual, is as good a place as any to get the specialty tools? Or are there places that sell used specialty tools?

I'm trying to anticipate issues to save time and acquire the tools if they are going to be necessary.

Thanks. Ken

 

[TR3driver]

Question 1: How necessary is it to use the special case-spreader tool that the manual suggests is indispensable. I have no machining equipment (or expertise) to make such a tool myself, and don't want to buy things that I will only use once or twice, if it can be avoided.

Not hard at all to build, if you have access to ordinary hand tools, can drill a hole, etc. Get a big turnbuckle for the forcing screw. However, it's also not really necessary. I've done several diffs without it. Here's a photo of the carrier coming out of my Stag differential. Note the pads used to protect the housing, as it takes a good deal of force on the big pry bars to get it out.

Question 2: Once I get in there, how necessary are the special pulling and pressing tools on the seals and bearings and such?

Unless you are just going to replace the thrust washers and seals, and leave the bearings and gears alone; then I'd say some special tools are absolutely required. Bearing separator, dial indicator, hydraulic press and so on. Those races are tight, and the shims have to be just so to build a diff that will last. And unless you have the magic factory pinion depth tool, there is a lot of trial and error involved as well. Even with it, you'll have to assemble, measure and disassemble several times.

Question 3: The manuals are not totally clear to me on the question of whether I should (or must) pull out the differential casing and then open and work on it without getting neck strain under the car. The manuals seem to assume that the whole thing will be removed, and it may become obvious (or unavoidable) once I'm in there and disconnect the drive shaft. Obviously, it will be a lot easier to work on if removed, but I don't want to invite other problems if removal is going to cause a chain reaction of issues.

My advice, remove it. You've already done the hardest part, getting the halfshafts & back plates off; and trying to work under the car is just not worth the grief.

Question 4: I assume that Moss Motors, my usual, is as good a place as any to get the specialty tools? Or are there places that sell used specialty tools?

As far as I know, Moss doesn't sell them either. You might be able to find someone willing to sell theirs, but I doubt it. Most likely, you're going to be stuck making your own and/or doing without.

I didn't document the entire process, I'm afraid, but here are a few shots to give you an idea. Here you can see my holding tool in the background, plus the bracket for a standard dial indicator to the right. (This step is determining the correct total shim pack thickness for the carrier bearings. Later you'll have to determine how many shims go on each side.)


Here is a modified gear separator, pulling off the head bearing


A stack of hollow items, being used to press the new head bearing back on


And a shot of how you know it's right.