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General Tech Rear Axle Spacer Shims—Solid Axle

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KVH

KVH

Obi Wan
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I think the Triumph shop manual rather clearly explains how to insert shims of various widths to achieve the axle end float specified in the manual. What confuses me is whether each side is to be set and measured totally independent of the opposite axle, or whether that opposite axle must first be secured with the bolts on the rear of the hub housing.

I ask because every time I measured after affixing the shims I felt were specified, the end float seemed to jump around and change. I know this is obtuse, but is it perhaps the case that measurement of axle end float cannot be checked or verified until and unless the opposite axle shaft has been inserted and tightened into place.
 
Both axles must be installed and the float measurement taken then. It is a bit fiddly. Its important to tighten all the bolts holding the axles to the rear end before taking the measurement. It is also important to get the shims very close to the same size on each side.
 
Okay, that makes sense. So, you do one side, leave the other side assembled. Tighten back up with new shims; then check the end float, then go to the other side? I'd need to pull things apart somewhat to recheck but that's what I did. I'm curious--what happens if you get off by a couple 1000ths? I did find the process cumbersome and don't recall, but seem to remember the shims not matching side to side.
 
KVH said:
Okay, that makes sense. So, you do one side, leave the other side assembled. Tighten back up with new shims; then check the end float, then go to the other side? I'd need to pull things apart somewhat to recheck but that's what I did. I'm curious--what happens if you get off by a couple 1000ths? I did find the process cumbersome and don't recall, but seem to remember the shims not matching side to side.
Click to expand...
Probably not the best way. But I decided that a viable way was to assemble both sides with the shims that came off and run the gauge. If out of spec open up both sides and add or delete shims to balance both shim packs.
Once all is tightened up. You should get the same reading when checking both sides independently.
Charley
 
If I’m recalling correctly the process requires a stock of extra tab washers. I did such a lovely job knocking mine into place last time. I’m forgetting how I mounted my dial gauge. It wasn’t easy.

I should be embarrassed to ask, but what are the side effects of having incorrect axle end float. (I’m asking for a friend:))
 
KVH said:
If I’m recalling correctly the process requires a stock of extra tab washers. I did such a lovely job knocking mine into place last time. I’m forgetting how I mounted my dial gauge. It wasn’t easy.

I should be embarrassed to ask, but what are the side effects of having incorrect axle end float. (I’m asking for a friend:smile:)
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My best guess is excess wear inside your pumpkin.
But I also think the tolerance is greater than we are lead to believe.
Charley
 
The axles rest against a thrust block in the center of the differential. At the outer end, they are located by the hub bearing's outer race. If there is too much float, it can result in more wear in the bearing and block; too little, and there will be too much of a load on the bearing, which also causes wear. If the float is not the same on both sides, it could push the thrust block to one side, which could wear the block and cross pin. So, it's good to get this right.

Since there is a certain amount of looseness between the thrust block and cross pin, you must have both axles in place to measure the end float. You might have to go back and forth between the two sides a couple times to make sure that the float is right, but it shouldn't require much more than that. That said, I don't remember it being very difficult to adjust.

The sizes of available spacers are such that you probably won't be able to get exactly equal-sized shim packs both places. I got mine within a couple mils, which should be OK, I think.

Also, I am very leery of the tab washers used throughout the car. Those are a bad idea left over from the 1960s. I use Belleville washers instead and Nord-lock washers in more critical locations. And, of course, I'm careful to torque them properly (the spec is 26-28 lb ft). I add some nonpermanent Loctite for good measure.
 
How do you get a torque wrench in there? I can’t even fit a small socket wrench. I had to use an open end hand wrench.
 
KVH said:
How do you get a torque wrench in there? I can’t even fit a small socket wrench. I had to use an open end hand wrench.
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By experimenting with a bolt and nut in a vise using a torque wrench and open or closed end wrenches. I get a close approximation of what it takes to get a particular setting.
There are lots of places that a torque wrench is not useable. One must learn to adapt.
Charley
 
You only need to install the tab locks for the final installation. They make no difference in the shim stack.
 
I’ve measured my end float. .006 passenger side, in spec; .002 driver’s side, out of spec. Obviously no good. I pulled the driver’s side and measured the shims. Clearly I goofed. I have spare shims of thinner stock, and I can equalize each side at .006 which meets spec.

I’m already full of grease. Many of you know the calisthenics involved getting into a cramped wheel well and loosening up those tab washers, etc. But according to the shop manual, equalizing the end float isn’t enough. The manual states that the washer thickness on each side should also be the same.

That means that, even if the mathematics works, I’ll next have to remove the passenger side axle and recheck the shims there. I do want to ask: If my end float is equal on each side, how big a deal is it to go through this last step of making sure that the aggregate shim thicknesses on each side are also, in total, equal?
 
CJD said:
Something like these adapters. They also come in open-end styles.

9-Piece Torque Adapter Set - 12-Point Box End Torque Adapter Extension Set - 3/8-Inch Drive for Hard to Reach Places - Includes 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8" - Amazon.com

9-Piece Torque Adapter Set - 12-Point Box End Torque Adapter Extension Set - 3/8-Inch Drive for Hard to Reach Places - Includes 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8" - Amazon.com
www.amazon.com
Click to expand...
I like this idea. I'll order a set. But, fyi, someone here once posted an article saying that lengthening a torque wrench changes the applied force and calibration. In fact, I think they posted a formula. Long time ago.
 
I don't understand how you can have different float on each side. Maybe I got it wrong but when I set mine up I would mount a dial indicator on one side, let's say the left. I then would shove the left axle in as far as I could, zero the dial indicator out, go to the right side and shove the right axle in as far as I could and look at the reading on the dial indicator to be from .004-.006. I would then shove the left axle in and make sure the dial indicator was at zero again. If I had to make adjustments I would do so on both sides in order to keep the shim packs equal in size.
 
Well, maybe I see what I did wrong. When I was .002 too loose on one side, to take an example, should I have added .001 to each side, and not .002 to the side measured?

FYI, my example, of course, is not very good. A shim .001 thick is not offered.

My original question was whether you adjust each side only after the opposite side was fully secured and bolted. It would appear the answer is negative. I think you are saying that both are left unbolted, unsecured, and equal shims are added to each side to the extent possible. A disparity of .008 would be made up by taking up .004 on each side equally.
 
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KVH said:
Well, I think I’m being told it doesn’t work that way. I’m told you have to secure each side while you adjust the opposite side. That is consistent with my actual experience, as well.

If one side is left unsecured, unbolted, then when you adjust the opposite side, and set it up to spec, it will change after you walk back around and do the other side that was left unsecured.

Am I wrong?
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Yes you misunderstand.
Just like the previous input-- you need to tighten both sides before taking any measurement. Then push the inner axle in and out to get your measurement. Measure both sides with the push pull and the measurements should be the same.
Proceed to equalize the shim pack on each side , tighten both sides and measure both sides.
Charley
 
Yes, I gathered as much. My edited post passed yours in the wires:

“Well, maybe I see what I did wrong. When I was .002 too loose on one side, to take an example, should I have added .001 to each side, and not .002 to the side measured?

FYI, my example, of course, is not very good. A shim .001 thick is not offered.

My original question was whether you adjust each side only after the opposite side was fully secured and bolted. It would appear the answer is negative. I think you are saying that both are left unbolted, unsecured, and equal shims are added to each side to the extent possible. A disparity of .008 would be made up by taking up .004 on each side equally.”

Measurements require that both sides first be bolted and secured. Hopefully correct now.
 
KVH said:
Measurements require that both sides first be bolted and secured. Hopefully correct now.
Click to expand...
And when you measure each side the measurements should be the same .
If not in spec then add or remove or swap out shims. I.e. swap a smaller for a larger to increase final measurement. You may only have to adjust one side to get it in spec. So it is wise to write down what shims you have on each side as you proceed.
Charley
 
Sorry, I should clarify a couple things.

Yes, when everything is set up right, you should measure the same float at both ends. That's because there is some clearance between the cross pin and thrust block in the differential. If you measure different floats at the two axles, the block is contacting the pin and you don't want that. Measuring both ends ensures that you haven't done that.

I'm not sure why Triumph specified equal-thickness shim packs. Probably to make sure that you preserve some clearance between the thrust block and pin. In any case, they don't need to be equal to the last mil.

Yes, the clearance is difficult for a torque wrench. I have a set of "crowfoot" wrenches for this. You do have to modify the torque when you use any kind of extension. It's easy to figure; if you increase the length between the handle and nut by, say, 10%, i.e. a factor of 1.1, the torque is increased by that factor, so set the wrench to 1/1.1 or 0.91 times the specified torque.
 
I could use more clarification. I measured my shims on both sides. They are exactly equal--.040 aggregate. But end float on the passenger side is .006, and on driver's side, .002. When measuring, I use the push/pull technique, but I note Mastaphixa above pushes in from the dial gauge side, zeros out the gauge, then pushes back out from the opposite side. Is that a more correct way? Does that account for play at the thrust block?

I realize I could probably just change one shim on one side, get reasonably close and call it a day, but here I am with all my tools on the floor, my radio blaring, and a bottle of diet coke to last 'til midnight. So, I'll await more responses.

Thanks guys!!
 
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