Changing Gears

[RLDSL]

LAbor for getting rear ends setup properly is not cheap . I went to school for a year on those suckers. You've got to pay if you really want it right .
( Ironically, today, I find myself in my old age rebuilding the posi on my truck and I've got the blamed thing together ...almost, and I find myself too damned weak to twist the pinion gears in past the pressure of the clutch plates anymore, and I'm about to load it up and run it by my buddys shop and see if we have enough oomp left between us to do it, if not, I'm going to have to go find a young fella to finish it off)

If you have a posi, that gets really fun to rebuild. You need to get into some creative tool making to be able to get them apart and reassemble them.

 

[13fcolt]

i swapped in a 3.55 on my 86 gasser about 10 years ago. bought a kit (sierra i think) that had everything except the tools and even then it was a pain in the ass. nothing really bad until it came time to install the new pinion. i managed to get it done but getting the pinion shimmed properly was enough that i'll just swap the whole rear end from now on.

 

[david85]

I swapped from 4.10s to 3.08s. Torque wrench was the only special tool I had.

The crush sleeve doesn't matter because you can get a solid spacer/shim kit to take the guess work out of the job.

In my case I ground the crush sleeve down slightly (measured accurately with a dial caliper) and then used a cheater pipe on a 1/2" drive pipe (essentually bench pressing the rear end of the truck while under it!). Definately not by the book but it worked. Loctite on all the bolts and the pinion nut are a strongly advised.

I would also much sooner just replace the complete rear end than pay some one to rebuild and swap gears over for you. Way too expensive.
Who knows, you might even find some one that is willing to trade you for the 4.10 rear end.

 

[Diesel_brad]

I swapped from 4.10s to 3.08s. Torque wrench was the only special tool I had.

The crush sleeve doesn't matter because you can get a solid spacer/shim kit to take the guess work out of the job.

In my case I ground the crush sleeve down slightly (measured accurately with a dial caliper) and then used a cheater pipe on a 1/2" drive pipe (essentually bench pressing the rear end of the truck while under it!). Definately not by the book but it worked. Loctite on all the bolts and the pinion nut are a strongly advised.

I would also much sooner just replace the complete rear end than pay some one to rebuild and swap gears over for you. Way too expensive.
Who knows, you might even find some one that is willing to trade you for the 4.10 rear end.

i am curious how you did the set up with out a dial indicator or a inch lb needle torque wrench

 

[david85]

i am curious how you did the set up with out a dial indicator or a inch lb needle torque wrench

All I did was swap the ring and pinion. Everything else went back in as I took them out.

To make sure the gears were tracking correctly, I used ink to mark them and rolled everything over by hand to verify proper gear mesh. My luck had it that the original shims gave me the proper tracking.

Don't know why a dial torque wrench is needed since all the bolts in there are big enough to warrant a 1/2" drive wrench.

Been about 50k miles since the swap and the only problem I've had is the pinion nut backing off but that can happen even on factory original sterlings. Loctite seems to have solved that problem though.

 

[RLDSL]

All I did was swap the ring and pinion. Everything else went back in as I took them out.

To make sure the gears were tracking correctly, I used ink to mark them and rolled everything over by hand to verify proper gear mesh. My luck had it that the original shims gave me the proper tracking.

Don't know why a dial torque wrench is needed since all the bolts in there are big enough to warrant a 1/2" drive wrench.

Been about 50k miles since the swap and the only problem I've had is the pinion nut backing off but that can happen even on factory original sterlings. Loctite seems to have solved that problem though.

Well you got a small part of it done correctly, but that's only part of it. You still have to get the pinion bearing preload and all the related fun with the new crush sleeve. just getting the pattern mesh is only [part of the battle . If it were that easy they wouldn't get so much to do it.

 

[david85]

If I ever take it apart again, I'll just get a solid spacer kit. That seems to be the simpler solution than the crush sleeve. I checked the pinion nut recently and its fine though so I might just run it.

 

[Diesel_brad]

All I did was swap the ring and pinion. Everything else went back in as I took them out.

To make sure the gears were tracking correctly, I used ink to mark them and rolled everything over by hand to verify proper gear mesh. My luck had it that the original shims gave me the proper tracking.

Don't know why a dial torque wrench is needed since all the bolts in there are big enough to warrant a 1/2" drive wrench.

Been about 50k miles since the swap and the only problem I've had is the pinion nut backing off but that can happen even on factory original sterlings. Loctite seems to have solved that problem though.

As RLDSL stated. You need the correct preload on the pinion bearing

 

[fields_mj]

I had mine changed this past winter. I picked up a decent set of used 3.55 gears on e-bay. I believe that the cost (delieverd) was about $30. I also ordered all my shims and spacers from Ricks Ring and Pinion. About $25 total from them, and they were able to tell me everything that I needed over the phone. Very helpfull. Labor to do the swap was almost $500, but this is my daily driver so having it done on time, and having it done right was worth the money to me. So all told, I had about $700 in the rear.

Now the other half of the story is that I had blown the seal and pinion bearing out of my D50 on the front end. I had a complete D50 with 3.55 gears that I had picked up off e-bay for about $100 delivered, so I had the shop do it all at once. Since it was winter time, I really wanted to get my 4wd working, and quick. I think the total labor bill was about $850, but I can't remember that well. Of course the two days I had the truck in the shop, I borrowed my folks minivan, and we got 10" of snow. Go figure.

 

[billyboy]

RLDSL: i hear you on that one. lemee guess.. 10.25/5 right?
like you say, posi reassembly is Brutal with that spring plate thing in the stack. don't need a gym membership when assembling those babies... for biceps anyways.

but i still love the chatter (spine tingling kind) of those tightly wound plates on terra firma corners indicating a well done set-up job. i'm doing a 10.25 right now, and have an idea for pressure plate assembly without too much stress. will keep you posted.

 

[MUDKICKR]

i usually charge to setup ring and pinions/rebuild them between 150 to 200. if you were closer i would rebuild that rear axle for 200 bucks, not including parts. or if someone had a drw rear axle i would do the labor for trade. i have a few 10.25 good axles here but not drw. the ones i have have a 3.55 a 4.10 and a 4.56 gears.

 

[billyboy]

just got that 10.25 posi together. it wasn't as bad as i thought, considering the strength of those bellville spring plates.

clamp an axle in a vice to hold the case. tie the bottom axle flange with a chain strung aroung the bench post (hopefully just below the vice) and connected to a flange hole with a bolt to keep it from turning. throw the carrier on the axle and spread the side gears apart with a threaded rod, a couple of nuts jambed on one end, and 2 more nuts and washers to seat against the inside side gears face. tighten the upper nut to spread the gears.

place the spiders to sit with one cog positioned just over top the edge of the concave washer face of the seat (so as not to catch). arrange them both on either side of the case. use grease to help ease them in.

the trick is to turn the case while the axle immobilizes the lower side gear, leaving the upper gear free to turn. for this, i used a piece of bar salvaged from an '80 F-150 4x4 steering link (center link). it happens to be the same dimension of the cross shaft - about 1". cut off both the threaded end and the ball joint end to leave about 3 ft. of bar. slide it in the cross shaft hole of one side, making sure it doesn't protrude into the spider seat.

with the axle shaft in a vice holding one side gear, turn the whole affair slowly. the spider gears walk in slowly about 1/2 the rate of rotation of the case. again, make sure your bar doesn't jamb the entry of the spider gears by sticking out into their seat and blocking them as they rotate into place.

i guess 1" bar stock works too, but had the linkage laying around for years. easy-peasy.