4:56 gears installed!!

[Geoff]

Finally got around to doing my gear install. Here's the new posi unit.

Cheap digital micrometer that seems to already be broken but worked long enough to measure the pinion shim.

Making setup bearings. Some say this wont give you accurate pinion depth for the final install but meh I say.

Setup bearings on new pinion

Ring gear installed

 

[Geoff]

Make sure you get the right carrier bearings if you have an 8.6 carrier, I didn't.

Securing driveshaft to gas tank strap.


Removed pinion nut with an impact.



Original gov loc carrier removed.

 

[Geoff]

Sanded the coating of the pinion where the bearings sit. I also honed out the outer pinion bearing a bit because the fit was so tight in it. I started out with the original shim thickness to start.



Heating inner pinion bearing to 275



Took me a good 2 hrs to get the correct backlash.


Checking my gear pattern with original pinion shim thickness and correct backlash.

 

[SunlitComet]

i hate to bum you out but you should never grind or sand or buff any thing on bearing contact surfaces and the bearings were supposed to be pressed on using a press. baking the bearing was not a good idea either.

 

[Geoff]

This is the tool I made to hold the yoke while I cranked to the new pinion nut to get the crush sleeve going.
Apparently angle iron from Home Depot isn't very strong. I ended up using vise grips with a piece of pipe on them.



This style of seal gave me trouble. I recommend getting the original style. Sorry I dont have a pic of that one.

 

[Geoff]

i hate to bum you out but you should never grind or sand or buff any thing on bearing contact surfaces and the bearings were supposed to be pressed on using a press. baking the bearing was not a good idea either.

I figured I'd roll the dice.

 

[Geoff]

i hate to bum you out but you should never grind or sand or buff any thing on bearing contact surfaces and the bearings were supposed to be pressed on using a press. baking the bearing was not a good idea either.

How tight is the outer pinion bearing supposed to be?

 

[Geoff]

All in all this took me about 13hrs to do with the wrong seal and breaking tools. I also set my shirt on fire grinding my angle iron yoke holding tool. I wish someone was filming that.

I cut the bearing off the old pinion to get to the original shim. I got lucky that the factory shim thickness worked out otherwise I would have had to buy a bearing separator.

I am well aware one should use a press when doing this job. I used a toaster oven, a hammer, and a pipe to get the lower pinion bearing on.

By the way the new gears are 4.56 with 35 inch tires.

 

[SunlitComet]

it take several tons of pressure so i would use nothing less the a 5 ton press for that. that is a lot of tightness.

 

[Geoff]

it take several tons of pressure so i would use nothing less the a 5 ton press for that. that is a lot of tightness.[/QUO

I thought the outer pinion bearing was supposed to slip on with a tight fit. The inner bearing needed to be pressed on.