Eaton HO72 rear axle

[RPOZ11]

Just picked this up
HO72 Detroit Locker rear axle
Drum to Drum
Here is the code and tag from it
Can anyone decipher the stamped code?
R JJG0761

Tag has no info on it

[RPOZ11]

Tag

[RPOZ11]

I'm also curious to the REAL name for these.
I'm seeing Rockwell Meritor
I was under the assumption that these were Eaton related.
I am seeing the R preceding the code for the gear ID.
I need to also look at the casted in part # also present.
So what is considered the official name of these?
HO52 & HO72

[RPOZ11]

Just found this:
Detriot Gear & Axle - G
G = Plant
G = Chevrolet G&A Positraction Carrier

[bw46]

You lucky dog! I have one of those but without the locker. I wish i could find a factory locker.
The Eaton rear ends are very sturdy. Only downside is that it's harder to find parts. But they're so stout they shouldn't break if reasonably taken care of.

[swamp rat]

http://67-72chevytrucks.com/vboard/s...d.php?t=590959

2nd page post 26, lists a chart for 72., your code:
Prefix: RJJ, Model: KE20, ratio: 4:10N,
*N designation is No Spin.

There is still a good possibility this is an HO52 not a 72, some Ho52's utilized the same ring gear and load bolt, the brakes were however larger.

[RPOZ11]

What an amazing amount of research you've provide.
Your link is pricless
TY

Ya, I'll assume its an HO52.
It does have the load bolt
Smaller brakes than what I have on the LongHorn

[RPOZ11]

Where do I find suppliers who actually stock the parts for these?
I found this link :
http://shop.cruiserparts.net/index.p...ducts_id=11557

I just helped a friend with going thru the LH brake system on one of these.
He needs a new lock retainer; as the previous owner(s) damaged it.
Im not sure where to locate this stuff.
And I have yet to begin on my HO72 in my Longhorn.
Thoughts..
Thx

[Shaky]

Originally Posted by RPOZ11

Where do I find suppliers who actually stock the parts for these?

Very limited parts availability for these. What kind of parts are you looking for? Seals and bearings are around. Gears - not so much.

[72freak]

Originally Posted by RPOZ11

Where do I find suppliers who actually stock the parts for these?

A lot of these parts are out of production, limited and hard to find. I finally pulled mine a few years ago and switched to an axle I could actually get arts for. It was a sad day but one that had to happen. Great find though!

[RPOZ11]

More part #'s :
Some may be available, Some may not be.
Some of this crosses over into 1973 and up.
It appears that GM continued using the same axle spindle dimensions.
The drums look to be obsolete now.

Axle Spindle nut (4):
Dorman 615-130
2"-16 thread

Axle Spindle washer (2) :
Dorman 618-048
2" X 2-5/8"
(on occasion, these may need to be clearanced on the inside diameter where it passes over the spindle. They are tight or do not pass over the threads. I had to de-burr the 2 Dorman washers that I used)


Axle spindle LOCK retainer (2) :
Dorman 618-049
2" X 2-9/16"

Axle Shaft Flange Gasket
(O-Ring or Seal)
Fel-Pro 55350

Hub bearings
Timken 388A (large bearing)
Timken 382 (large bearing race)
Timken 368S (small bearing)
Timken 362 (small bearing race)

Rear Hub Seal :
National PM2081
National 710568 (Escalade)
The Escalade seal above resolves the 2081 from leaking due to wear grooves that occur on the landing area for the housing.


Differential cover gasket :
Clevite P-39130
Mahle P-39130
Victor (Reinz) P-39130
JEGS 695-P39130
Fel-Pro RDS 5088

Drop Out Carrier gasket :
Fel-Pro RDS 5090

Pinion Seal :
Yukon YMS411330N
Part # : 807-YMS411330N (JEGS)

Pinion Shims :
Yukon SK20100
Part # : 807-SK20100 (JEGS)

Yukon Differential Bearing Kit :
Yukon BKGMHO72B
Part # : 807-BKGMHO72B (JEGS)
B - denotes "Load-Bolt"

12" Brake shoes:
Wagner Perfect Stop # PSS248DR

[RPOZ11]

Original Lock retainers

Original brake adjusters (His are locked up)
Using a calcium lime soluition, this was submerged for 24 hours and it freed up the adjuster.

Original drain plug (His was damaged)

[RPOZ11]

So, when I'm actually looking up parts for these,
I there a parent name it all falls under?

When I research the internet,
I typically type in HO52 or HO72.

Could there be a more main title all the parts fall under?

These go back years, and I'm unsure the production years for the HO72 release

[suprachrgd82]

This thread is a great read. Long, but full of info about these axles.

http://www.pirate4x4.com/forum/chevy...aton-h072.html

[RPOZ11]

Thanx !

[RPOZ11]

Ive looked up more about these.
(Work so much that it takes me a while to make some progress on this)

Yukon offers a Master Overhaul kit using a Tapered Pinion Bearing for the Load Bolt design :
https://www.yukongear.com/productdet...px?ProdID=4271
If you have the HO52, then I suppose you can sell that thrust bolt to us here on the site.

Randy's offers up the same kit :
https://www.ringpinion.com/b2c/Produ...px?ProdID=4271

So, with some further research, it appears that Timken is the bearing brand provided in this.
Looking up Timken, they may be a US company, but they do manufacturer items they sell via offshore locations.
This part might be made here in the USA, China, India, or who knows whatever new factory that they contract with.
Most readings I find suggest opening up the packaging and determine where it was made.
You may get 2 bearings where one is made here and one somewhere else.
No consistency.

The small parts I am seeking I am still researching.
got a lead on these small parts...
will advise asap

[TCCGRIZ]

Has anyone done the disc brake conversion on there Eaton as described in one of the links . If so any part numbers ?? They used stuff from a 14bff I believe . I have 2 k20's would be a nice upgrade .
Thanks

[RPOZ11]

As I've come to understand it,
I believe that the FF 14-Bolt aftermarket brackets bolt right up to these.

I'd consider doing it but I really don't want to disturb my factory brake lines.
My truck, I plan on keeping it all original; mostly.

However, I do have this extra HO52.
I am looking into swapping in the FF 14-bolt side gears and installing the Detroit unit.
If that all works as suggested, I just may move forward into installing that disc brake setup.
In do time.
Gotta buy up these parts first.

[RPOZ11]

Started tearing into this axle today.
GM ring gear part # : 3934647
Ratio : 10:41
Date : 2/1972
Pics

[RPOZ11]

HO52 Drum, Hub assembly apart
The 12 X 2-1/2 drum GM # is 3998512
The Hub GM part # is 3988535
The bearings found installed are :
KOYO 388-A
Bower 368 or 388-S (can't determine yet)
Seal part # is 2081

Anyone have any input on the outer beating part numbers?

[RPOZ11]

Figured out the lock retainer :
Dorman 618-049
Brand new

[Tdrcreyn4]

subbed

[RPOZ11]

Ready to reassemble ...

[B. W.]

You may have already found this info. The tag denotes what type of differential, can't remember if it's gear ratio or locker/open/ limited slip. GM used different shaped tags with no data on them to differentiate differentials (yeah, that was a play on words)

[RPOZ11]

I do still have the tag from it.
No info present on it.
As suggested, the stamped code on the drop out defined its build.

We are currently in the process of sizing up all the bearings for fit.
Paint up the hubs then install the bearing races for it.
Waiting for the disc brake brackets to arrive so we can try that on this.
Still need to buy the calipers, rotors, brake lines, and rebuild the Ring & Pinion.
Going to try the 14-Bolt Locker & 14-Bolt axles.

Its all new for me.
My first attempt at doing a rear axle