1969 Imperial progress thread

[vdk2010]

PART 2/2


The original Shim underneath the inner Pinion Bearing Race was damaged from hammering out the old Race. Unfortunately, in the Doctor Diff rebuild Kit, there were no shims to replace it. But there were Shims to go underneath the Pinion Bearing itself.
In my Mind, it doesn’t matter if the Shims are underneath the Race or the Bearing itself. The position of the Pinion Gear inside the Housing should be the same. Is that correct?

Since my Bearing Race installing tool was not big enough, I had a fitting disc laser cut to press in the Race.

Using the Setup Bearings, the Pinion Gear went into the Housing.

What’s the correct order to reassemble and adjust everything correctly now?
Is my List correct?

1. Setting up a baseline with Shims to set the Pinion Depth
(measuring the stock shims and use the same thickness as a start)

2. Checking and setting up Carrier Bearing Preload.
Setting it by turning both the adjusters with a Spanner Wrench towards each other.
But how do I check it?

3. Checking and setting up Ring/Pinion Bachlash by turning both the adjusters the same amount on each side until the Backlash is.. what?
The Book gives me three different ranges on different Chapters of the book.
.005 – .0015
.008 – .012
.06 – .08

4. If everything is set, I have to check the tooth contact pattern with the yellow grease.
If it’s wrong, it’s another story of its own... But first things first…


I hope someone can answer all the Questions (marked in red) I have so far.

Thanks!

 

[detmatt]

I wish I could help but I have a friend that does these things for me so I’m out…

 

[3175375]

Is this procedure covered in the Factory Service Manual (FSM)? I would suspect that it is.

 

[Big_John]

I’m going to use Green Bearings when assembling the Axle.

Just recently I've read, that when I do that, I don’t have to use the thrust block in the middle of the sure grip.
Now, my question is, do I HAVE to remove it or is it optional?

You should be able to leave the spacer in with no problem.

Why are you using green bearings? The adjustment of the stock bearings is a piece of cake and takes less than five minutes. I'm not a fan of the green bearings.

 

[vdk2010]

Is this procedure covered in the Factory Service Manual (FSM)? I would suspect that it is.

The description in the FSM is using a bunch of special tools, which I don't have which makes it not practical for me. Besides that, the questions I still have are mostly about deviations of the standard anyway.
I've read the chapter in the FSM multiple times and I'm more confused every time I read it. :/

 

[vdk2010]

You should be able to leave the spacer in with no problem.

Why are you using green bearings? The adjustment of the stock bearings is a piece of cake and takes less than five minutes. I'm not a fan of the green bearings.

I bought them in a package deal with a bunch of other C-Body parts from someone who finished his project and since I did not have new tapered bearings at that point I decided to use what I have since there is no downside in using them afaik.

 

[Big_John]

I bought them in a package deal with a bunch of other C-Body parts from someone who finished his project and since I did not have new tapered bearings at that point I decided to use what I have since there is no downside in using them afaik.

The downside is the green bearings aren't made to take a side load like the original bearings are.

Now... There's a ton of guys that use them and they say "no problems", but most of them are lighter cars and there's also folks that will point to the way new cars are built. However, the green bearings are just a standard ball bearing that isn't designed to take a side load and not a bearing designed for that use (like in a new car). The first sets of green bearings, sold through Chrysler always had the "drag racing only" warning in their catalog. Somewhere along the line, guys that didn't understand how to adjust the axle bearings started using the green bearings (IMHO).

 

[vdk2010]

The downside is the green bearings aren't made to take a side load like the original bearings are.

Now... There's a ton of guys that use them and they say "no problems", but most of them are lighter cars and there's also folks that will point to the way new cars are built. However, the green bearings are just a standard ball bearing that isn't designed to take a side load and not a bearing designed for that use (like in a new car). The first sets of green bearings, sold through Chrysler always had the "drag racing only" warning in their catalog. Somewhere along the line, guys that didn't understand how to adjust the axle bearings started using the green bearings (IMHO).

I heard that as well but then I've read somewhere, from Dorcor Diff himself iirc, that they changed the bearings by adding the o ring and the snap ring which eliminates that problem. But I'm no expert on that and I'm not fixed on using the green bearings when everybody says to not use them on daily driven C-Bodys.

 

[Big_John]

I heard that as well but then I've read somewhere, from Dorcor Diff himself iirc, that they changed the bearings by adding the o ring and the snap ring which eliminates that problem. But I'm no expert on that and I'm not fixed on using the green bearings when everybody says to not use them on daily driven C-Bodys.

I'm no expert on it either.

I've read pros and cons.... I haven't found an advantage to running them in a street car. In a drag car, yes... Easier set-up with a center section change. In all the arguments I've ever seen or heard, no one with knowledge of rear ends has ever said that the stock set-up is weak or prone to failure (other than improper install). One caveat is the use of good Timken bearings over some of the offshore replacements.

Having seen different failures of axles over the years, I tend towards doing what I feel is correct. YMMV.

 

[vdk2010]

I hear you! I will think about it, thanks for your input!
RockAuto doesn't have the Timken Bearings listed for my Imperial, but hat the Timken SET 7 available when searching directly for it...
SET 7 is the correct one, right?

 

[vdk2010]

I'm no expert on it either.

I've read pros and cons.... I haven't found an advantage to running them in a street car. In a drag car, yes... Easier set-up with a center section change. In all the arguments I've ever seen or heard, no one with knowledge of rear ends has ever said that the stock set-up is weak or prone to failure (other than improper install). One caveat is the use of good Timken bearings over some of the offshore replacements.

Having seen different failures of axles over the years, I tend towards doing what I feel is correct. YMMV.

Thanks John, for your input! I've ordered the entire tapered Wheel Bearing kit from Doctor Diff!

 

[vdk2010]

I've read the text in the FSM over and over again (which is btw the same as the text in the book I bought. surprise, surprise) and when I understand it correctly, preload is simply set by reducing backlash?!
When it gets very technical, there is kinda language barrier sometimes...

So the procedure seems to be,
1. Setting bashlash to .006 to .008 as a baseline.
2. Setting backlash to .0005 to .0015 to set preload on the carrier bearings.
3. Setting bashlach back to .006 to .008 as a final setting using the ring gear tooth side adjuster only.

Can someone answer my question about location of the shims underneith the pinion gear instead of the original shim underneith the bearing race?

From the FSM:

DRIVE GEAR AND PINION BACKLASH
Correct drive gear and pinion backlash when properly set is .006 to .008 inch at point of minimum backlash.

(1) Attach a dial indicator Tool C-340 or C-3339 to carrier flange so pointer of indicator is squarely contacting one drive gear tooth (drive side) (Fig. 31).

(2) Measure backlash between drive gear and pinion at four positions, approximately 90 degrees apart. After point of least backlash has been determined, mark drive gear.
Do not rotate drive gear from point of least backlash until all adjustments have been completed.

(3) Using Tool C-406A (spanner wrench) turn both bearing adjusters equally (in same direction) until backlash between drive gear and pinion is .0005 to .0015 inch.
This backlash variation is given to permit alignment and installation of the bearing adjuster lock, lockwasher and attaching screw.
The adjuster must only be turned in a clockwise direction and under no circumstances should be backed off.

(4) Install adjuster lock on bearing cap, back-face side of drive gear. Tighten lock screw to 15 to 20 foot-pounds.


DIFFERENTIAL BEARING PRELOAD

(1) Turn bearing adjuster (tooth side of drive gear) (Fig. 32) in a notch at a time (notch referred to is the adjuster lock holes) until backlash between drive gear and pinion is a minimum of .006 to .008 inch. This will preload differential bearings and establish correct backlash.

(2) Tighten the remaining two differential bearing cap bolts to 85-90 foot-pounds.

(3) Install remaining adjuster lock, lockwasher and attaching screw. Tighten to 15-20 foot-pounds.

 

[vdk2010]

NOS? NOS!

 

[65sporty]

Yes you can put the shim under the race or bearing, most are under the bearing. Dana puts them under the race

 

[vdk2010]

Yes you can put the shim under the race or bearing, most are under the bearing. Dana puts them under the race

Thanks!

I'm pretty sure the rear end was never open before. So apparently Chrysler has put the shim underneath the race from the factory as well back in the day?! Interesting.

 

[vdk2010]

Bringing her home!...

install the stub frame and the rear axle to get her on her own feet, then install the doors and fenders, align them properly and then she goes back to get painted on the outside!

 

[vdk2010]

Now that she is back home I started right away with assembling the rear axle so I can put her on her own feet.

 

[vdk2010]

 

[vdk2010]

 

[vdk2010]