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TR6 TR-6 U-Joints/Half-shafts

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Bob_TR6

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Greetings:

I am in the process of replacing the U-Joints in my '73 TR-6 half-shafts. My shop manual (the TR6 ROM, from leyland) is a bit thin on the details that I am looking for.

Torque spec for the flange bolts (inner and outer)-- 34 Lb/ft with new nyloc nuts. Sound right?

I am planning on separating the half-shafts, and cleaning/re-lubing the splines--any suggestions for the lube? I was just going to use a high-temp bearing grease. Are the half-shafts interchangeable left to right?? Would there be any benefit to swap L to R (if they are interchangeable?) Even out the wear?

Also--I've noticed that when accelerating into a corner, the car will take a 'set' until you let off the gas--then you can feel the rear twitch and settle. (which usually makes me twitch..and settle:smile: ) Normal? I assume that the half shafts are binding under acceleration--which is why I am looking at cleaning and lubing them.

Thanks--

BobH
 
My manual doesn't specify a torque setting. I always tighten as much as possible using two combination wrenches.
As a grease, I would use a high tack grease that is going to stay in place. The higher tack greases also act better as a shield to dirt. Lucas Red Grease is a good quality product.
I don't see any advantage to swapping half shafts.
The twitch you are experiencing sounds more like a differential bushing problem. Switching to urethane bushings should solve the problem. I would avoid the original rubber type bushing because the reproductions don't hold up well.
 
Thanks Doug-

I did put new (repro) bushes in when I had the diff out to re-seal it. Guess I'll add urethane bushes to my next order. (That usually occurs right after I actually take something apart... :smile:
 
The twitching is almost certainly binding half shafts/ slip joints. This is a known and documented issue for the IRS cars.

Last summer I pulled my diff to have it rebuilt and resealed. As you, I used it as an opportunity to pull apart, clean, inspect, lube and reassemble the half shafts. Half shafts are technically interchangeable left to right. Some do this to balance wear. I chose not to. As far as lube, I used Sta-Lube EP Moly Graph Multi Purpose Grease. I chose this b/c of the molybdenum and graphite content. Really slippery stuff! Plus, the label states "contains rust and oxidation inhibitors". (There, advert finished).

Certainly, use new nyloc nuts on the flange bolts and get them real tight with two combo wrenches. My Bentley workshop manual states "Inner Driving Flange to Inner Axel 100-110 lbs/ft".

Bob
 
does it matter if the shafts are not reattached to the diff flange in the same orientation as they were when they came off? in other words, are they balanced?
thanks
c74
 
i did some research on this a while back and decided on Honda Moly 60 paste. it is made for driven spline joints and is the hot ticket w/ BMW and other shaft drive bike owners. it is a little tough to find though and $10 or so for a tube that is enough to do a a few cars.

for the inner flanges, the torque is pretty important, a long time ago i had some loosen up probably because of the PO's improper tightening and their use of fully threaded bolts. make sure that you have the proper bolts with the correct size grip length and i recommend using all metal locking nuts as opposed to nylocs. i went w/ AN bolts and on the last one I did.

good luck, w
 
++1 on the "proper" bolts, with machined shoulders.
I've never seen or heard where orientation is important at the axle to differential flanges regarding balance.
 
wingsandwheels said:
i did some research on this a while back and decided on Honda Moly 60 paste. it is made for driven spline joints and is the hot ticket w/ BMW and other shaft drive bike owners. it is a little tough to find though and $10 or so for a tube that is enough to do a a few cars.
Click to expand...
Here's one source: https://www.casporttouring.com/store/merc...duct_code=23500

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]i recommend using all metal locking nuts as opposed to nylocs. [/QUOTE]
Me too. I use the "oval lock with conical top" type at https://www.mcmaster.com/#catalog/116/3185
 
Did you replace the trailing arm bushings at all?
They make a big difference to how these cars corner particularly when applying power out of the turn.
 
Thanks, gentlemen--

Did the one side this Saturday (the passenger side), and am going to let the other go for a bit--it's not as bad (yet). I used a high moly grease on the splines.

Oddly, the u-joints on the side I did were 'mismatched'--one had no grease fitting, and they both used different types of circlips. I'da thought that as long as you had the thing out, you'd replace both ujoints.

Also--Any opinions on the whether the'boot' that protects the inner u-joint has any value? Mine both seem to be a bit melted-from the previous exhaust system, I think...Worth replacing? I think that if I just keep 'em greased, it shouldn't matter, hey?
 
IMO, keep the boot.
 
My inner Ujoint boots were in shreds and I just abandoned them in the end; mostly because I hadn't ordered replacements and wanted to get the job finished, I reasoned that they really don't achieve anything except making it more difficult to pull up the bolts to the diff. Thay was 5 years ago and I haven't regretted it yet.
 
Note that TR4A IRS rear axles did not have the boots. I recall considering adding them as protection for the inner U-joint when I restored my TR4A but I don't think that I did.

Scott
 
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