Mike's 1973 D22 Complete tear out. From the Roof down!

[RockwoodMike]

I need to paint the gas tank(Main)..so it was soda blasted..Then Rustolium rusty metal primer..

Same thing with the top of the differential..then when they dry, I can roll it over for the bottom side..

So while everything is drying, I decided to open up one of the front brake hubs and see how they look.

Bearing numbers are....

Timken 25520 Large race
Timken 14274 Small race
Timken 25590 Large bearing
Timken 14116 Small bearing..

As for the seal..no markings what so ever..So I went to National seal and bearing..Found their catalog
and with a shaft of 2.44" and a bore of 3.625..4th picture says it is a 3210

They are everywhere...

https://www.ebay.com/itm/154930638636..

I can't find where I got it but it interchanges with a SKF 24459

https://us.rs-online.com/product/cr-seals-skf-/24459/73210724/

This SKF has a leather seal to it..Never seen one of those before..

I bought the 3210 seal with the rubber seal..

As for the bearing/races...Rock Auto...Just put Timken (number) and it will come up with several sellers..

Ebay (Sorry MLW) has many sellers too..

Now I get to hurry up and wait for the parts to come in.. 

[RockwoodMike]

This rotor is an oddball..Can't find it anywhere..12.25 wide by 1.5 thick.

The rotors are in good shape so I don't need to replace them..

Everything I find is 1.125 thick with a 1.118 discard width..

These have a 1.485 discard originally 1.5 new..These are 1.5 as is so I am good..

Couldn't find them new though..

[Eyez Open]

Simply outstanding work, actually I'm having second thoughts on my rebuild...Ok second thoughts over. I absolutely detest heavy rearend work, axle grease would be one of most profoundly disgusting oders known to mankind.

Carry on I am waiting for you to assemble the rear end. It will be the first time I've ever seen it done. I would very much like to have put a different ratio in my 33 but..no experience at all there.

[DaveVA78Chieftain]

Are you sure you do not have a R400 (RM350) chassis?
Per the Service Manual (Page 5-23):
R/RM-300 Rotor: 1.170 - 1.190 Thickness
R400 (RM350) Rotor 1.520 - 1.550 Thickness

[RockwoodMike]

https://www.partsgeek.com/wmvzymm-dodge-rm350-brake-rotor.html

Dynamic Friction 119642-05971802

Thank You Dave!! I think I will be okay with the rotors that I have but by looking for a "RM350" which only seems to show up as a 1974 part, I found this part linked above..

The problem with finding this part number, is none of the listings have sizes listed..

[DaveVA78Chieftain]

The trick with this is that you have to follow the Centric 120.67011 path for information. Unfortunately the Centric site itself only shows info for the R/RM300 part 120.67004.  R300, R400, & R500 chassis all have different size rotors.

Via google I found the following old info

Centric 120.67011

Info

[RockwoodMike]

Sorry for the long time since last posting..Came down sick..Just getting over it..

The differential isthe project to get on and finish..Here goes!!

With the diff all painted, time to install parts..

Pic 1 is looking down the pinion shaft area..small bearing race goes in first..no shims or anything.

Pic 2 and 3 shows the small race showing both sides.

[RockwoodMike]

Put a little grease in the area where the race goes..little on the race and the race just taps in with a brass punch..go easy with the blows to tap it in..if it is straight, it taps right in

[RockwoodMike]

Main bearing onto the shaft of the pinion..

It is a press fit..or not..

If you have a press..you use it when the bearing is room temp..

Or heat the bearing..I did 300 for 30 minutes..Had the shaft ready on the table and the bearing just fell on and down the shaft..no press was needed

[RockwoodMike]

There is where the fun starts..

I found a nice picture from the web..It really shows what we have to set up..The Pinion Height..

And a Dana 70..the distance from the top(Button) of the pinion to the midpoint of the bearing caps for the ring gear carrier is suppose to measure 3.5 inches..

So the gauge reaches down to the pinion..add the thickness of the plate that the gauge sets on

My plate is .178 thick..plus 3.5 inches for the distance...3.678 is what I need to be perfect..

Shims under the big race installed is what make the height adjustable..

Problem is the race is installed with a brass drift like the small one..

If the shims are wrong then you get to pound out the race to adjust the shims..usually in up wrecking the shims doing that..

So you make a race from the old race that has been filed down on the outside to make it drop into the bore..that way there is no damage to the shims..You just reach in to the race and lift it in and out by hand..

You can see how the outside of the race was ground dwn using a flapper disc of my hand grinder..

It is called a setup race..once the distance is set then you install the real race with the proper shims..

Originally the set up had a oil shield shim and 4 other shims to add up to .050 thickness..

Always keep the original parts especially the shims to get you close to what was the setup of the old parts..To help you set up the new parts..

[RockwoodMike]

The way I started to find the perfect 3.5 inch pinion height was install the pinion and it's bearings without any shims

That involves both bearings and races and then tighten down some to squeeze the bearings tight in their location

Checking the height, I figured I was too low by .059

[RockwoodMike]

So I created a shim stack that was .060 all together..

After all that I was too tall for the pinion..I had 3.672 for the height..It needs to be 3.678..About .006 difference..That can make for a poor meshing of the teeth..

[RockwoodMike]

Took the shim stack back out and made a stack that was .055 and that hit the height it needed..

You end up doing this sometimes several times till it measures out..

After all that was done, then I installed the new race and double checked the height again and it was just fine!!

[RockwoodMike]

Now for the preload of the pinion bearings..In other words how tight to squeeze the bearing together to eliminate all play and not have them too tight so that they burn up..

Shims..how many thousands of a stack of shims do you need to get it just right..

Pic 1 shows the original shim stack and they were beaten hard because they were loose..couldn't even measure them to see what they were originally..

Pic 2..Here is the shims from the kit and other ones I had on hand..I just installed a stack as a guess..

Pic 3 shows what I tried first

Pic 4 shows where they are installed on the pinion shaft

[RockwoodMike]

I must have tried 15 times trying to get the perfect preload of 20 inch pounds of torque to rotate the pinion..

Too tight..too loose ..way too tight..way too loose..then when I was ready to quit for the night I tried one more stack and hit it!!

You need an inch pound torque wrench after you tighten the yoke nut down to 250 pounds..

Sometimes the pinion would be super loose, other times you couldn't turn it at all..

It was a hassle but I got it at 20 inch pounds to turn the pinion..

Now I need to set it all up for the ring carrier and its preload ad backlash..

We are having fun now !!

[RockwoodMike]

Time to work on the Ring carrier..The big center section that holds the spider gears..that is the set of gears that allow your wheels to spin in a different rate to allow you to go around turns..And it holds the 41 gear ring..the big ring that meshes with the pinion..

Got to clean it first..I have a 5 gallon bucket with mineral spirits in it..Just soak ll the parts in there for a day or so.

Pic 1 shows everything that is filthy dirty..

Pic 2 shows parts being pulled after soaking

Pic 3 shows everything laid out..Still pretty dirty..

I bead blast next

[RockwoodMike]

Pic 1 and 2 show front and back of the part that bolts the ring to it

Pic 3 and 4 show it after baking soda blasting it..Then it is scrubbed in the sink with Simple Green..

Gotta watch out for the bolt holes..The soda will pack into the holes..Water and compressed air will clear them out..

[RockwoodMike]

Everything all clean and laid out for assemble..

[RockwoodMike]

Assemble of the ring gear assemble..This is the thing that spins on 2 bearings..holds the big ring gear and has the spider gears that allow the wheels to spin at different speeds as you go around a corner..

Pic 1..shows how the 2 piece case is split and marked for assemble line up to the marks shown in red.

Pic 2..this is the piece that holds the 4 spider gears..it has 4 spider gears and the later model one piece carrier only has 2..notice the wear on one side of the shaft and hardly any wear on the other..Because the hi wear is the side that drives the wheels forward..

Pic 3...First is the piece that splines with the half axles..Has a thrust washer and then just drops in..

Pic 4..Shows it in place..35 splines to match the half axle shafts..

[RockwoodMike]

Pic 5..shows the 4 spider gears laid in..

Pic 6..Shows the other spline gear laid on top of the spider gears and the top piece ready to be set on it..

Pic 7..if everything is right, then the top piece just sets on to nice

Pic 8.. shows the 8 bolts that hold it together installed and snug tight..Need to be torque to 70 pounds..
Need to install the big ring gear now..

[RockwoodMike]

Pic 9..The ring is a press fit that is done with the 12 bolts..you just have to line it all up as you tighten the bolts down evenly, it draws the gear towards the carrier for a very tight fit..these 12 bolts are just snugged down..110 torque for them

Pic 10..The side bearings need to be properly shimmed..No idea what I need as the original were shown to be destroyed..This is why I am doing all of this to fix the bad stuff that would have caused troubles..I started with a .030 shim on each side..it will need more to set it all up

Pic 11 shows the bearing being press on..this can be done with light blows if you don't have a press..I press it with the race on top to protect the thin sheet metal bearing cage..

[RockwoodMike]

Pic 13..shows a tool called a "Case Spreader"..What it does is allow you to open the case by.010 to.015 to help you load the ring carrier..Got to be careful not to stretch it open to much or you can damage the case..It just spreads it that little bit to help you drop the carrier in..

Pic 14..just shows the races in place..gives you an idea of how it is set up..

Pic 15..The races need to be on the bearings and you just set it down careful!!
Install the bearing caps..

Pic 16..With a pipe wrench on the yoke, you can now hold everything tight as you go around the carrier and torque all the bolts down properly..
The manual shows the carrier in a special vice to hold it properly to torque all the bolts..Installing it in the case holds it for you and the pipe wrench keeps anything from spinning while you torque it all down..

[RockwoodMike]

This is where you are really tested..In the process of tightening the 8 bolts of the 2 piece carrier halves, one of the bolts snapped..Only 70 lbs of torque and SNAP!!

the bolt was fatigued..All the others torqued down just fine..Had to take it all out, take it apart but was easy enough to get the snapped off part out with a pair of vise grips..

I thought I was SKEE Rude!!..Just got to stay calm and think it though..

I am going to replace all 8 bolts..If another snapped off while driving, it would just grenade in there with you on the side of the road waiting for a tow truck!!

This stopped me from going any further till I find some bolts..7/16-14..2 inch long..Grade 8..

[RockwoodMike]

Here is the top of the bolt..I think it is grade 8..A grade 8 washer to go with it..

I am glad it snapped..being towed off the side of the freeway and then getting fixed by Bubba in his road side repair shop would be expensive!

[Eyez Open]

When the bolt snapped..Thats a very lonely place to be in.. As you have said..better now than later. You just saved many thousands of dollars in the long run..