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Discussion Starter #1
First of all, I don't need to change the rear wheel bearings so I don't need to troubleshoot if the bearings are bad.

I was reading through the TSRM looking at the procedure (yeah, I lead a boring life...) and noticed that the procedure calls for measuring the bearing pre-load. It seems pretty straight forward until I looked at the torque specifications for the measurement.
Rear Wheel Bearing Pre-Load Measurement from TSRM.jpg
Page RA-10 on the On-Line TSRM

http://www.cygnusx1.net/supra/Library/TSRM/MK2/manual.aspx?S=RA&P=10

1-4 kg-cm (0.9 - 3.5 in.-lb., 0.1 - 0.4 N.m)

How on earth do you measure 0.1 - 0.4 N.m? This calls for a REALLY special torque measuring device.

For those of you who have done this, did you really measure the pre-load or go "Close enough for government work" after spinning it by hand? I'm really curious for some honest answers.

I've found some Torque Screwdrivers with 1/4" drives that can measure them but generally they are REALLY expensive.

Do auto shops carry these or again, is it done by feel?

For the record, the lowest cost tool I've found is US$165
CN50DPSK Torque Screwdriver.jpg
This is a Japanese tool. English or German tools are U$500 and UP!!!!!

http://www.bestool-kanon.com/items/~torque-tools~/torque-screwdriver/dpsk~dial-gauge/newton-meter~cn-m~n-m-/cn50dpsk-detail.htm

For those of us (I mean me) metric challenged, 1 cN is 'one centi-Newton' which is 1/100th of a Newton. Therefore the range of this tool is 10 cN.m to 50 cN.m which is 0.1 N.m to 0.5 N.m.

Would a real mechanic laugh at me for actually considering getting one of these if I ever needed to do this or is this a standard tool that a mechanic would have?

Digressing further, the crush bearing spacers are no longer available so for someone having to make up shims to set this tolerance, I would think this is a pretty important measurement.

Dale
 

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I used a fish scale on one of the lugs, however I could never hit the specs in the manual. I started out way over the value they want. Mine ended up coming loose after some miles so I went back in a retightened the nut by feel to eliminate the slop in the wheel bearing.
 

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Discussion Starter #3
I used a fish scale on one of the lugs, however I could never hit the specs in the manual. I started out way over the value they want. Mine ended up coming loose after some miles so I went back in a retightened the nut by feel to eliminate the slop in the wheel bearing.
That's what I was thinking. These values are so low that almost anything could skew the results. The viscosity of your bearing grease because of the air temperature when you are measuring it could probably change the reading 50%.
 

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Years ago I rebuilt a differential and I bought a KD Tools 1/4 inch drive fixed beam type torque wrench to set the preload which as I recall was supposed to be something similar, like 2-4 in lbs. The tool was 0 - 60 in lbs range, marked off in 2 inch lb increments which worked just fine. Don't know how accurate the tool is at that level, but the diff was still going good after a few years when I sold the car. Since then I've used that torque wrench for a bunch of fasteners that have small torque settings, like bolts on stamped sheet metal valve covers, that I used to do just sort of hand-tight.

https://www.centurytool.net/2955_KD_Tools_Torque_Wrench_p/kdt2955.htm
 

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I used a fish scale on one of the lugs, however I could never hit the specs in the manual. I started out way over the value they want. Mine ended up coming loose after some miles so I went back in a retightened the nut by feel to eliminate the slop in the wheel bearing.
This is pretty much what I did sans fish scale. No issues but not much mileage either.
 

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I hope that you never have to do this job. The crush spacer is discontinued, and the amount of force it takes to get the parts disassembled is incredible.
 

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Might want to try looking for a used bearing, hub assembly and control arm as one piece and just swap the entire thing out. I did that to mine and got the job done in one hour and also got an alignment. Took me 6 months to find it and had to live with grinding noise the entire time. No press or torque wrench to deal with. I saw another one on Craigslist a few weeks ago and I just went back to look for it and it is gone. Got mine for $75. I got really lucky.
 
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