[jjmt]

Now stick the indicator to the face of the differential case (where the cover goes) and set the tip of the indicator needle on one of the ring gear bolts on a flat and then ZERO the indicator (pic143b) now gently rock the ring gear back and forth and take the reading from the indicator (pic143c) it shows .003” of back lash. It should be .008” to .012”
That’s TOO tight the gears will whine like a B***H and burn up! So I need to move to carrier away from the pinion .006”
So now remove the bearing caps and pull the shims on the ring gear side and measure the shim thickness (pic146)the shim is .280” thick I need it to be .274” thick so now I picked out some shims from the supplied shims (pic145) and stacked them up till I got .274” (pic147) Now remember what ever you take off from one side you have to put on the other side to keep the preload on the bearings

[jjmt]

Now put the shims back in (you will have to tap them back in to place) they should fit in VERY SNUG (pic145a) put the bearing caps back on and snug them down then position the indicator and zero it out (pic148a) now gently rock the ring gear back and forth with out making the pinion move and read the indicator (pic148b) now after changing some shims I am now in tolerance at .010” the specs call for .008” to .012” so I am right on the middle.
Now remove the indicator and get the marking compound and the brush and PAINT about 4 teeth on the ring gear (pic149)

[jjmt]

Now turn the pinion shaft by hand and rotate the ring gear a couple of times going forward and then backward (pic150) then look at the paint marks (pic151) it shows the contact point to be right where the specs call for in the center.
Now turn the gear a little more so you can see the “heel” mark(pic154) now turn the ring a little more so the you can see the paint mark on the “DRIVE” side (pic153) all is good to go now its time to torque the bearing cap bolts to 85 foot pounds (pic 169)

[jjmt]

Now the new gears are in their new home its time to finish up by putting the axles back in but clean off the bearing surface first (pic171) slide the axle back in till its all the way in (pic172) now clean the “C” clips off (pic173) now that you have the “C” clips cleaned and the axles pushed all the way in you can now insert the “C” clip on to the axle (pic174) where my finger is pointing too. Just slide the clip on to the axle (pic175)

[jjmt]

Make sure that you push it all the way on till it bottoms out on the axle (pic176)

[jjmt]

Now use a screw driver to push the axle back out so the “C” clip will go in to its pocket (pic177)
Do the same for the other axle,
Now make sure that the spider gears lined up with the shaft bores on the carrier (pic178) and (pic179) now insert the spider gear shaft and line up the pin hole (pic180) then put the put the locking pin back in and snug it down(pic181)

[jjmt]

Sung the locking pin down with a wrench (pic183) then torque down to 25 ft pounds
Pics # 184 and #185 are just pics so you can see how it looks when done and 185 is so you can see the paint on the gears

[jjmt]

Now that you are done with the gears rebolt the support rod back to the frame (pic186)
Put the drive shaft back in place and bolt it back together and torque em(pic187)
Now clean the diff. cover and the bolts and put the gasket on the cover(pic188)
Put the diff cover back on and tighten the bolts starting from the bottom (pic189) working your way up one at atime so you don’t warp the cover
Now remove the filler plug using the square end of a 3/8” drive ratchet with a 6 inch extension (pic190)

[jjmt]

Remove the plug and clean the magnet (pic191)now fill the diff back up with synth.lube
It will take one and half quarts I used the Ford lube
That’s it you are now done with the gear install …
Put the rotors/brakes/etc/wheels back on the remove the jack stands pick all the tools up and clean up .
When you are done with all that grab your X-cal 2 and plug up to the car (pic194) and tell the car your new axle ratio (pic195) so the Speedo will be right

[jjmt]

Now back on out and go for a test drive (pic196) I went about 10 miles at speeds from
20 mph to 60 mph (NO BURN OUTS YET) it was a successful install (pic197)
it took me about 9 hours over a period of 5 days to complete and yes it was not hard but tidies cause everything had loc-tight on it and if you don’t have tools and a place to do it you will be better off having a shop do the install( here in San Antonio the average price for the install was from $800 to $300 plus parts ) like I said in my other post I am not a mechanic and I do not work on cars , I make my living as a proto type machinist and have been doing it for over 25 years and I have a very very good understanding of how things work especially machines of any type and are cars are Machines

[lavrishevo]

Jim you rock, I am impressed... I don't think I have the guts to take on that project even though I have rebuilt two engines. But one thing... how about that lawn my friend? If you only had the same enthusiasm for lawn work. I kind of imagine myself like your dog there, napping while some else scrapes the crap out of their hands.


DW

[jjmt]

All ready getting the pm's
ok some of you have asked how much differant my rpm's are ?
Yes ther was about a 300 rpm diff. at 70mph
look at he pics below pic # 999 is at 70mph with the stock 3:55 gears and pic#1000 was at 80mph with the stock gears
and pic # 1001 is at 70mph with the new 4:10 gears and so is pic#1002 at 80 mph with the 4:10
And pic#1003 is the box the gears came in

[Kyle F]

Holy crap, I cant believe you did this in your driveway. This is definately one fo those "it has to be right" installs that I felt was worth the money to have someone else do.

Great Job Though and very nice pics and instructions.

[jjmt]

Hey Mick i put the stock, "puimpkin" cover back on for now till i get an aftermarket one

[drjeff]

This is an old thread but I have to comment- I love reading these installation reports! I have no intention of ever replacing the gears myself, but I learn so much from your descriptions and photos about how my car works. Great job and thanks!