8-1/4 bearing pre load tool

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boilermaker

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I am looking for info to build a bearing pre-load tool. What size is the hex on the cups?
I think a big nut welded to a piece of pipe or bar?
Any input much appreciated!

John
 
I am looking for info to build a bearing pre-load tool. What size is the hex on the cups?
I think a big nut welded to a piece of pipe or bar?
Any input much appreciated!

John
I forgot..... 8-1/4 1974 Dart thanks.
 

At 11:17 in this video, this service technician shows a 36 mm nut with a 5/8 spark plug socket welded into it, it looks simple enough to make. This may need to be double checked because this is a newer jeep rear axle, another person on the tube used a 37 mm nut for the same purpose.
 
I found a big bolt I had in my bolt bins that was a little bit to large to fit in the adjusters. I took and ground down the flat sides at a taper angle til it would fit the adjuster but not go thru it. I then used a 7/8" socket that just fit the threaded end of this large bolt. I then welded it to the bolt. I use a long 1/2" extension thru the tube openings to set backlash. If I were home I would take a picture of it.
 
I'm upgrading my 8 1/4 right now. A FABO member told me what to do. I made 2 of them from 36MM Subaru axle? nuts from auto parts store, 32" 1'2"pipe and 1/2" socket adaptors. Weld together and they work great. If I remember, the nuts were $9.50 a piece, I had the other stuff laying around.
 
I did same thing,axle nuts from fwd cars, pipe and a socket on the outside end welded to pipe. Two makes adjustment much faster. Way less fiddling.
 
I found a big bolt I had in my bolt bins that was a little bit to large to fit in the adjusters. I took and ground down the flat sides at a taper angle til it would fit the adjuster but not go thru it. I then used a 7/8" socket that just fit the threaded end of this large bolt. I then welded it to the bolt. I use a long 1/2" extension thru the tube openings to set backlash. If I were home I would take a picture of it.
Same here
 
I built one of these using Ace hardware plumbing supplies, wooks perfect
 
I built one of these using Ace hardware plumbing supplies, wooks perfect

I had 2.set one in each side. Left them at the dealership when i moved on. Probably still in the same corner where i left them. Nobody there was the least bit interested in dealing with rear ends.
 
Weld a 36mm nut on the end of an old torsion bar. Done.
 
The c body t bar is a perfect fit.......did this many times.

No doubt you're correct. The A, B and E body hex ends translate to a tick over 31mm and all the info I've found says the C body bars hex "is larger" than that, so I bet you're right on the money.
 
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Another option, for us labor intensive types. A short piece of this Speedy Metals 1-7/16" 12L14 Steel Hexagon grind and file .010 off each side, drill the center and tap 3/8-16 6 threads deep. Run in a long piece of the cheapest 3/8-16 all thread you can find and jam nut it down, jam nut with sleeve nut on opposite end. Make two and hang a 9/16 reversible gear wrench off of each end while you are setting everything up. Or maybe just get someone else to work on it...:lol:
 
Another option, for us labor intensive types. A short piece of this Speedy Metals 1-7/16" 12L14 Steel Hexagon grind and file .010 off each side, drill the center and tap 3/8-16 6 threads deep. Run in a long piece of the cheapest 3/8-16 all thread you can find and jam nut it down, jam nut with sleeve nut on opposite end. Make two and hang a 9/16 reversible gear wrench off of each end while you are setting everything up. Or maybe just get someone else to work on it...:lol:
Preload is 75 foot lbs if i recall, 3/8” all thread will pretzel.
 
My Bad! In my haste I forgot about torque requirement for pre loading the backlash into the case... My original thought was 1018 round stock welded on with a nut welded onto the end. It would take a 5/8 inch bar due to torsional loss along a four foot length but it's still doable for cheaper than the aftermarket tool. Four feet length at home depot or the like for $15. The engineering math comes out to close to 270 lbs of torque yield strength for a 5/8 diameter piece of 1018 cold rolled low carbon alloy. But over a four foot length your going to have a lot of flexing and twist built in so you would want the extra fatigue resistance of the extra material.
 
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