And Anti-spin Swap
replacement rear end OUT of the car: Unbolt the retainers on the ends
of the housing. Get an axle puller (Auto Zone will loan one to you) and
jerk out the axles. Clean those nasty axles, press off the old bearings
and retainers and press on the new bearings and retainers. Then go put
those axles in the corner. It will be a while before you need them.
But first go try to stick them into the posi carrier you have to make
sure the axle is the right diameter and has the correct number of
Next remove the old axle seals and replace them with new ones. You will
need a seal puller or a slide hammer with an attachment. The seals are
pressed in the end of the axle housing. The best way to press them back
in is to find a socket that is rhe right diameter and hammer them back
into the axle tubes.
Next unbolt the cover plate and drain out all that old fluid. Next you
have to pull out the old carrier. Clean off the caps that hold on the
carrier with a good degreaser like alcohol. Then before removing the
caps be sure to mark them as right and left or whatever. Be sure also
to know which end is top and bottom. I used fingernail polish.
Markings is necessary because these bastards are line bored after
assembly. This is line bore thing is important to remember. Now take
out that greasy carrier. You may have to pry it out. It also helps if
you turn the pinion gear it will help lift the carrier out of the
Now it is time to take out the pinion gear. The hardest thing will be
getting the pinion nut off. I would soak it down with WD 40 or Liquid
Wrench. Then get an impact wrench to get the pinion nut off. Of course
you will have to find some way of keeping the pinion from turning. Once
the nut is off, get a big hammer and smack the pinon gear. It will
eventually come out of the housing. Do not screw up and smack the yoke.
You mihgt want to get a piece of wood and put it on the pinion and hit
the wood instead of trying to hit the rear of the pinion while trying to
miss the yoke. Once the pinion comes out, pry out the pinion seal. You
can do this with a dull chisel or screw driver.
Next you will have to remove all of the old bearing races from the
housing. There will be a notch in the housing at the rear of the race
where you can get a punch in there to knock out the race. Actually
there will be two notches. Now press the new bearing races into place.
For this I found some really big sockets and an extension. I put the
socket on the race and proceeded to hammer away. This was a major PITA
for me because the rear end was still in the car. There are two bearing
races in the carrier. The rear and front pinion bearings. Now get your
new posi carrier and press the bearings onto the carrier. Go ahead and
put your ring gear onthe posi carrier if it is not already on there. Be
sure everything is clean. Be sure to put in the new pinion oil seal.
Now the fun begins. If you have a richmond gear there will be a check
distance engraved on the face of the pinion gear and a backlash
measurement engraved on the ring gear. These are CRITICAL numbers. If
not you will have to use some general numbers. I think factory backlash
is .005. My Richmond gear backlash was to be .008. If you have too
much backlash you will know in a hurry. When you drive down the road
and let up onthe accelerator you will get one loud whine.
The check distance is the distance from the centerline of the ring gear
to the face of the pinion gear. This is one MF to measure. Technically
you cannot do what you think is right. That is: lay a flat piece of
metal across the face of the two caps and measure down to the face of
the pinion. The reason this is not accurate is because the saddles are
line bored. The caps are not exactly split in 1/2. Unless you have a
pinion depth setter, you may just have to use the above method and hope
for the best. However, if you do not have a check distance dimension
you will just have to do it like this. I am going to ASSUME that you do
not have a check distance dimension. In that case do the following:
If a shim came off of the pinon gear, put it back on the new pinion
gear. Then press the rear pinion bearing up on the pinion shaft untill
it is tight against the rear face of the pinion and shim. Then put the
crush sleeve on then put the front pinion bearing on. The front pinion
bearing is not pressed into place. It is held in place by the yoke.
Then slide this mess back into the housing, put the yoke on and tighten
it up slightly. You tighten up the yoke untillit takes about 15 INCH
pounds to turn the pinion gear. OK assume this is done.
Now it is time to put the new posi carrier in place. Try to hold the
races on the bearings and put it in the saddles. The ring gear should
engage the pinion nicely. Now comes the trial and error BS. You put
shim packs on each side of the carrier untill you get the proper
backlash on the ring gear and the proper paint pattern. Once you THINK
you are close, get some gear marking compound and apply it to the ring
gear. Be sure to put your caps back on and torque them to about 65 FOOT
pounds. Double check that torque I am doing this from memory. Once
you have everything in place and painted up turn the pinion gear and see
what pattern you get on gears. You are looking for a rectangular
pattern that is even across the drive face of the ring gear. I am sure
it will not be right the first time. Now you get to move shims from
side to side untill the pattern is correct. Then check the backlash. I
kinda did mime backwards. I got the backlash right and then checked the
paint pattern. It turned out to be perfect when the backlash was
correct. I also was able to measure my check distance before I ever
put in the carrier. But I am assuming you can't.
Once you have the paint pattern anb backlash correct, you are good to
go. Put everything back together and drive off. And listen. If you
have strange noises. TRY AGAIN. Be sure to use a good lube and put
the limited slip additive in there or you will get chatter and grabbing
and such. Do not use synthetic gear lube!
The most critical part in all of this is getting the correct gear teeth
mesh. Take your time with those shim packs. Of course if you have
crappy luck like me and your pinion depth is wrong, you will be screwed.
You will have to take the pinion gear back out and put in the right
shim to adjust the depth of the pinion in and out.
[ Thanks to John Harris for this information ]
Clutch Plate Anti-Spin
I can see no reason why a rebuilt clutch plate type posi can't be rebuilt
good as new. This assumes no obvious mechanical failures which would
otherwise render the unit useless. It is/was common practice among drag
racers to take a brand new unit and tighten it up as much as possible by
using thicker plates and other means. If the car is street driven, you
must use gear lube formulated for posi units.
[ Thanks to Bob Handren for this information ]
Cone Plate Anti-Spin
It is also a cone type posi unit. If that is shot it
cannot be rebuilt in the same fashion as the plate/friction type. They can
however be made functional with a little work.
[ Thanks to Bob Handren for this information ]