[nsaness]

The pics are super helpful

 

[sherlock9c1]

If you recall before I disassembled the axle, I measured end play and it was something ridiculous like .055". The passenger side measured 0.021."

Driver's side also measured 0.021". 30 thou may not seem like a lot, but with my Eaton, it made all the difference. This posi should still have some life left. If you are looking at purchasing one of these cars and want to judge how much life is left in the posi, Take off a wheel and measure the end play. 0.008" is absolute best-case min. This only works for the factory cone-type posi and the Eaton-style clutch posi. Worm-gear style will never wear out, but they are also not tuneable. If that's the case, just jack up one wheel, put the transmission in neutral and measure the torque required to turn it. Factory spec is 40-100 ft lbs. I'd say 100 ft lbs is ideal for a healthy one.

Reinstalling the yoke bolts for safekeeping. I've always used 11mm on these; are they 11mm or is it really 7/16"?

Next steps are to add the brake lines, bump stops, ABS wire bracket and other miscellaneous bracketry.

 

[Navy Lifer]

Well lookathat. The GM gasket does NOT cover the holes.
View attachment 209825

But 30 seconds with a pair of scissors fully opens those holes. It's just paper, people.
View attachment 209826

One other point - I seriously considered just buying new Dorman covers and not dealing with rusty factory ones. But the factory ones hug the ring gear much better, promoting oil pumping against the cover, AND the sides are shaped to channel oil to those big holes. OK, years later, case closed. We were all correct. The holes are for case spreading AND for lubrication. The GM gasket DOESN'T have holes but it DOES allow for lubrication even if you don't trim it.
View attachment 209827

Several things to consider here - the importance of the OE cover design, with the magnet & stamped steps. Many have opted for a non-OE cover, some without either of these features.

1. The magnet on a drain plug won't capture near as much material as this (OE) magnet.

2. In Post #309, small holes are visible near the carrier bearings that direct lube into that area - though there is no photo in this series, the axle housing center casting has a channel in the top that captures and sends lubricant to the pinion bearings and carrier bearings. Essentially, all of these details describe the function of a pump, with the ring gear as the main character in a centrifugal pump, flinging lubricant outward and into the cast channel of the housing and to the steps in the stamped cover.

3. The stamped "step" on each side of the OE cover is a functional part of the lube system - the ring gear picks up lubricant while the vehicle is in forward motion, and constantly pushes it against this cover, which serves, to a certain extent, as a heat transfer surface (ie. cooling). Lube also gets channeled toward the 2 holes by the shape of the cover

4. Since gear lube is thicker than motor oil, and the amount of fluid in the housing is not as great as either the engine or transmission, the steps in the cover are to direct some of the lube out through the holes in the housing (those covered or uncovered by various OE & aftermarket gasket designs) - this will also create lubricant circulation out into the axle housing tubes, to force lube toward the wheel bearings, as well as further cooling effect of the lube passing into & along the housing tube itself.

5. I won't challenge the gasket issue, and we could conclude that GM acknowledged their error by re-designing the gasket at least twice since the B-body 8.5" axles were built. The FelPro gasket included a slotted passage for lube to pass, so maybe they realized something that GM had missed. I often have wondered if that slot was to meter the flow, instead of having the path "wide open" between the lube reservoir (diff cover) and the rest of the axle assembly.

6. A vehicle in motion does derive some movement of lubricant through not just pumping actions, but also in turning left & right, on angles (road surface not flat), etc (ie. sloshing). If there was a wheel-bearing seal leakage issue, or concern, there could have been a decision at some point to use the cover gasket to limit or stop flow via the diff cover step & housing holes, to stop or reduce lube going out into the housing tubes, to "fix" a bearing shaft seal leakage problem.

 

[95wagon]

Just for fun , buy brand a new GM cover after about 2003 and see what you get.

 

[Navy Lifer]

Just for fun , buy brand a new GM cover after about 2003 and see what you get.

exactly....probably costs less, and/or they determined that the notches moved too much lube where it wasn't wanted or needed! Goes along with the revised gasket configurations.

 

[95wagon]

Or the different dia side bearings of the 8.6 vs the 8.5 with came about 98 ish ?

 

[sherlock9c1]

@Navy Lifer and @95wagon I appreciate the conversation. I just checked on Rock Auto for a '96 Impala and EVERY non-GM 8.5" gasket has the slots. The GM gasket as pictured above has no slots but the case openings are only partially covered.

The slotted gaskets are cheap. Do you think I should swap in one of those?

 

[Navy Lifer]

The slotted gaskets are cheap. Do you think I should swap in one of those?

Joel, I don't think it matters at this point - just so the holes aren't fully blocked.

 

[95wagon]

Meh , maybe a little dot of sealer here to make it more of a collection point like the slotted gasket does.

That said if the slot is cheap and available,
Lining the two up and studying them might be enlightening for you and the blob of sealer you could be playing the too much or too little game

 

[sherlock9c1]

@Navy Lifer @95wagon I'm just wondering if I'm going to have too much flow to the axle tubes now? The only obvious return path I see is out the top holes just outboard of the bearings; there doesn't seem to be much room for lube oil to return THROUGH the differential carrier bearings.

EDIT - Then again, if I get leakage with brand new seals and good axles, that'll tell me that I need to swap gaskets, which is easy but messy.

 

[95wagon]

I would not be worried.
Look at the giant grooves in a 12 bolt cover
Look at the TA cover.
Moore law here for me.

 

[Navy Lifer]

@Navy Lifer @95wagon I'm just wondering if I'm going to have too much flow to the axle tubes now? The only obvious return path I see is out the top holes just outboard of the bearings; there doesn't seem to be much room for lube oil to return THROUGH the differential carrier bearings.

EDIT - Then again, if I get leakage with brand new seals and good axles, that'll tell me that I need to swap gaskets, which is easy but messy.

don't over-think this, just make sure the lube level is correct before going overboard with worrying about a non-issue. GM & AAM built these things for a long time, there are no magic tricks. One change I can think of is the triple-lip seal setup that was part of the service pinion flange kit, but even that wasn't perfect, from some reports. Make sure the housing vent is working properly, too.

 

[95wagon]

I drank the triple seal Cool Aid with one of my diffs.
The set up , to me , looks more like protecting the dust and oil seal lips from outside elements.
As in trucks wandering around in mud and dirt.
I think a properly installed seal works fine.
Just make sure not to use a front diff seal as they are directional

 

[sherlock9c1]

Boy I love north Alabama weather. 67 degrees F (20 C) today and perfect time for painting some remaining parts before reassembly. Fuel tank heat/crash shields wire brushed, degreased, primed and painted.

While I was at it, I painted the wagon’s driveshaft safety loop. This Krylon Rust Tough enamel goes on so nice and lays down perfectly. I highly recommend it.

Next up was the rear swaybar. Rusty and nasty, so I wire brushed it, then derusted it with phosphoric acid. Ready for primer:

Primed with Rustoleum Rusty Metal Primer:

Man these sway bars are tricky to paint. Lots of angles. Two coats minimum just to make sure you hit everything.

 

[96 Black]

What can be more enjoyable on a craptastic cold windy Sat. morn. than catching up on the last half-dozen pages of all the work getting done here while just setting back with a cup 'o joe?

 

[sherlock9c1]

I got the transmission almost out last night. Hopefully another 30 minutes of work and I'll have on my fancy transmission stand. I'll test and fix the pressure regulator valve in the pump, do a quick inspection on the guts, and put it back together and reinstall. It sure is nice to work on rust-free bolts with only 3k miles on them. But I have second thoughts about loctite on the bellhousing bolts. They didn't want to budge!

 

[95wagon]

"loctite on the bellhousing bolts"
That's a new one for me .

 

[sherlock9c1]

"loctite on the bellhousing bolts" - That's a new one for me .

It was a suggestion by someone I trust. I will adjust my "good idea" filter settings.

 

[95wagon]

Good flange head bolts , or ARP hardened washers , torque wrench , never had back out.
Even on our odd fire v6 race car !

Loctite would be good for cowboy install where the bolts are maybe tight maybe not .
The 18 year old me would laugh at the 66 year old me and the things I torque.

 

[Leo1979]

Meanwhile I started prepping parts for cleaning and painting. I disassembled the throttle body for painting. How about that '96 Dexcool/Stopleak duo, eh? View attachment 197463