Finally got the 4.56 gears and TruTrac posi installed in the truck. I actually have power again. After a couple of years running around with 3.55 gears and 35" tires. It's almost like half way between HI and LO range. After break in, drove on the interstate and was able to use OD again and go around someone with it still on. With the new ratio the gear changes are like having a shift kit compared to what it was before. The only isuue was the rear axles were worn under the bearings and had to shell out another $350 for new axles. The posi unit is quiet and does not click or grab. The front vacuum actuator has some cheap 1/4X20 bolts that hold it on. Three out of four broke. No big deal though. Now do I want to add another 3 inches and go to 38's or get the speedo calibrated. Way off the other way now.

 

yea you have to love the power difference. when i had stockers with the manual trans it wasnt bad at all but i can only image what its like with the auto. also how much did it cost you?

 

The rear was $300 labor and $85 for misc. stuff, gear oil, case of brakleen, axle bearings.
Then there was the unexpected $350 for new rear axles. They had grooves under the bearings.
The front was $290 for all since I helped and did the most of the labor.
Normally the job would run $700 to $800 for both axles and then parts. Got the buddy discount.

Now I know how the sleeve collar works and how easy it is to pull the front axles out.
Replaced those cheep rusty, only one didn't break, 1/4"X20 actuator cover bolts with stainless steel.

After watching the guy set the gears and carrier shims, I definately would not try that job myself.

 

scary isnt it?

i watched a budy set up his rear diff for his dirt track racer.. PITA... defenatly wouldnt monkey with it myself...


i would do the front.. since it doesnt have to me as exact as the rear..but the rear is like a tranny to me... will not tear into it

 

The rear is actually way easier. the only thing you have to shim is the pinion.

 

Yes it would have been a lot easier if I had just swapped the gears on the rear but the rear posi unit was a whole new carrier and the front carrier had to be changed to accommidate the gears. Just a gear swap would have saved a few bucks but a posi is a must when needed.

 

I was actually replying to Shott. He said he would rather do the front gears instead of the rear.
Therear is much easier. easier to take apart, more room to work on it and easier to set the backlash.

 

Chopper, I do have a question for you though.
Did you replace the axle shafts or the axle tube?

 

Deffinately the rear would be the prefered one to work on given a choice.
The axle shafts were worn under the bearings. About 4 to 5 inches from the back plate. I guess it was easier than smoothing them down and getting off sized bearings.
The guy said he only sees this in heavy use work trucks that are loaded down or carry trailers with a lot of tongue weight, or if they are run low on lube. He said the lube level was fine, which was original so that ruled that out. Maybe it was a combination of the tractor I towed to the mountains, the 20' husdon trailer I hauled to the other side of W. Va. to carry a car back, or the 16' enclosed motorcycle trailer going down I95 at 80 to 90 MPH with the truck and trailer loaded down a few times. Or just my luck....

 

What do you mean "worn under the bearings"?
the axle bearings wore into the axle shaft?

I dont understand your wording.