Longhorn Rearend Eaton or GM...I need a real gasket!!!!!

[stllookn]

Looks like an Eaton but I can't find it in my Chassis rebuild manual and the restoration manual is no help. 4.57 ratio however 7/32. I went to NAPA to get a new gasket and all they had was a very thin piece of paper that fit...said Dana on the package!!!!!! This does not look like a Dana casting or cover (round)! This thing had a cork gasket on it but I can't seem to find a replacement cork gasket. Thought I would ID the rearend first.

[Americanrider]

Yea, it's a Eaton... clean it good & just use Blue RTV.

[stllookn]

Boone, Thanks. I am trying to do the 100 pt resto on this one so I think I am going to have to make a cork gasket. I hate being this picky! The good news is that it looks great and tight inside...WHOOO HOOOO!

[Longhorn Man]

Just use sealant. I like The Right Stuff. Expensive, but it works. (and the OEM's all aprove it too)

[oldiron]

Try Randy's Ring and Pinion. Use their 800 # ext. 5552 Tell Opie I told you to call. He is real good to work with.

[stllookn]

Thanks guys...good suggestions. I will follow up. I was hoping to button it up today but it is raining for the first time in months so I guess we work in the garage tonight.

[Longhorn Man]

it's raining in washington??? no way!

[4x4Poet]

I recently bought a thick, round, paper gasket from NAPA for my '72 K20 pickup's Eaton rear cover. Still in the package. I could pull the part number tomorrow, if needed.

BTW, NAPA also sells the paper gasket that goes between the Eaton's third member and its axle housing. That, also round, gasket is thin paper– probably to keep the side gears properly aligned with the centerline of the inserted axles once the third member is torqued down.

[stllookn]

The one the guy tried to sell me...and I refused to buy was that thin paper gasket! What a joke...I could have traced it on paper myself. I seriously thought it was the paper that was on the cork and someone just pulled the cork gasket out and left the paper inside.

Yes...I would like that part number if you have it.

[Chris H]

I have swapped a few Eaton 3rd members around, and I believe that these used a "paper" gasket from the factory.
I have used Permatex Ultra Black with good results, but it does not look absolutely original.
Do remember to use some kind of thread sealant on all the bolts, they go through the housing into the oil and will be quite messy in short order if not sealed. Dont ask me how I know this

[stllookn]

ChrisH, Good point. I pulled those bolts and watched the oil drain so I know what you mean. I will have to clean out the bottom of the housing before anything will seal those threads. The good thing is this baby is tight and looking good. I love when the PO takes care of the equipment. Some guys just never change the rear end oil!

[Dean]

I think GM did use the thin gasket. All I have ever seen when I pull them apart plus I ordered the gasket from GM and I got the thin one.

[stllookn]

Dean, Thanks...I guess I will have to use that one. This is why I love this board...eventually we can kick this thing around enough to make a good decision.

[D.PASSMORE]

I have a few NOS ones. Cork. They are stashed away in a out of the way location. Take a week to drive over and lay hands on them. PM me and we can work out something.

[stllookn]

I am interested depending upon the price. I am in no rush at the moment since I will probably need to clean and paint the entire rearend eventually when the restoration gets further along. Right now I am just getting it back on the road and addressing the "drivability" issues.

Mike "stllookn" Kirby

[D.PASSMORE]

Let me know... Oh yeah, US Gear sells rebuild kits for these type Eaton Rear ends. I sure it is a HO72, adjustable load bearing bolt on the front side of differential?

[4x4Poet]

Turns out I bought an Eaton H052 rear axle housing cover gasket from BTB:

Felpro RDS 5088 Rear axle housing set
Chevrolet Truck
1937-1972
Replaces 3665606

I have my '72 pickup's Eaton H052 rear cover off, so I lined up the gasket. Fits perfect. All precut holes line up. And I thought the gasket was paper, but it is ~1/16" and both thick and rubbery, like it is rubber impregnated paper. Definitely not cork. Not just smooth rubber. It has a texture. I'm not sure what it's made of, frankly.

D.PASS, Some H052s can have the ring gear deflection bolt in the side of the third member housing. I have a '71 K20 burb with 12"x2" brakes and a '72 K20 pickup with 11"x2.5" brakes and they both have third members with the side bolt adjustment. I'm guessing the deflection bolt came on later model H052s. I'm still learning about Eatons.

[zimmm]

NAPA/Victor Part No. for the rear gasket is P39130. This will be the heavier gasket material, but not cork. Just went through the same thing with my truck as well. For the 4x4's the catalog has the front and rear gasket parts numbers reversed.

[stllookn]

Looks like my adjustment bolt is on the side. Does that mean it is an HO52 or HO72?

[Robert1970C20rstbukt]

The rear end in my truck has the load adjusting bolt on the side too.

[1969 GMC]

Originally Posted by stllookn

Looks like my adjustment bolt is on the side. Does that mean it is an HO52 or HO72?

Your truck is a 3/4 ton, right? So its a H052. H072 was basically the same axle that came under one tons.

EDIT: the gear deflection bolt may be a newer thing. my '66 centersection doesnt have it, but my '68 does.

[stllookn]

1969GMC, Thanks, that is good to know...3/4 t. - Eaton HO52. I noticed that my '72 3/4 t. Longhorn has a Dana. I guess the General used whatever arrived on the next pallet...LOL!

[4x4Poet]

Originally Posted by zimmm

NAPA/Victor Part No. for the rear gasket is P39130. This will be the heavier gasket material, but not cork. Just went through the same thing with my truck as well. For the 4x4's the catalog has the front and rear gasket parts numbers reversed.

I have NAPA P39130 Eaton H052 cover gasket in my hands and it is only ~1/32" thick. Compared to the Felpro RDS 5088 gasket I'm holding, the NAPA/Victor Reinz P39130 gasket is only half as thick as the Felpro gasket, so I'd say the thicker Felpro version will more easily conform to irregularities in the cover/housing or different bolt torques and thereby seal better. They're made of the same stuff, though [rubber impregnated paper? Still don't know.].

I also have NAPA and Felpro Eaton H052 3rd member gaskets. NAPA P29129 and Felpro RDS 5090. They're about the same. Both thin paper, but the Felpro seems a tad better. Tough call.

I'm taking back both NAPA gaskets. NAPA's cover gasket for being half as thick as Felpro's offering and also NAPA's 3rd member gasket since I'll only have to make one return. Besides, I've already opened the Felpro boxes, but not the NAPA plastic wrap.

Thanks for the thread, stllookn. I might not have noticed the differences had you not brought it up while I had all 4 gaskets in hand with my H052 cover off. Felpro kicks @$$ this time. Now where's that receipt?

[Robert1970C20rstbukt]

I had to buy a big sheet of cork/rubber gasket material and make one. All I could find were the thin paper ones too, but then I screwed up and didn't put sealer on the bolts so it leaks like a SOB. I'll just wait to fix it right when I change the gear oil again.

[jostrans68]

like this?fel pro rds5088 at schucks