8.5” Posi rebuild?

[Sherif]

I was planning on removing my axles today to instal my disc brakes and ARP wheel studs but I couldn’t get the c-clips out. I man-handled it and I broke the “s” spring (somehow) that sits between the gears. It seemed weak to begin with...

Does anyone know where I can find a rebuild manual on how to rebuild this posi unit? Or can I just order a new spring and somehow pop it in?
Never messed with a differential before but since I broke the damn thing I gotta fix it somehow. thanks!

 

[pacecarta]

you can get an s spring from gbodyparts.com
key to getting it out is before you pull the cross pin out is rotate pinion until the back of the s facing you remove cross pin push axles in and clips fall out then pull axles out of the way of spring and just pull it out , new one just hammers in
you should not have had to mess with the S spring to get the clips out ..all you needed to do is once the cross pin is out just push the axles in and the clips fall out

 

[bpman1234]

Yup..

 

[Sherif]

you can get an s spring from gbodyparts.com
key to getting it out is before you pull the cross pin out is rotate pinion until the back of the s facing you remove cross pin push axles in and clips fall out then pull axles out of the way of spring and just pull it out , new one just hammers in
you should not have had to mess with the S spring to get the clips out ..all you needed to do is once the cross pin is out just push the axles in and the clips fall out

ahhh ok thank you for the reply. I did just that and was able to pull it all the way out. I just ordered a new 's' spring...thankfully i can just hammer the new one in without taking anything else apart.

 

[Sherif]

Is the wear patterns on my axles in ok condition? I can’t feel much of anything with my finger when I run it across the surface but if you zoom into the picture it kinda looks like there is ever so slightly pitting of the surface.

 

[hensleyt]

Time for a set of axles.

 

[hensleyt]

I do have factory manual was looking last week at , think there is a pdf floating around somewhere

 

[earlbrown]

I've got a set of factory GM service books that have all that data in them. What year is your car (not that it matters, the sets are the same other than the cover)?

 

[Pronto]

Might was well go with stronger axles while you're there.

 

[Sherif]

Any axles recommendations you guys like running? I know lots of guys like mosers, any other options? My new build should be somewhere around 500rwhp and is ONLY street driven(no track)

 

[Mr.Spool]

Any axles recommendations you guys like running? I know lots of guys like mosers, any other options? My new build should be somewhere around 500rwhp and is ONLY street driven(no track)

28 spline is all you will need

 

[Sherif]

I already bought ARP wheel studs for my stock axles. Will these wheel studs fit in the moser axles?
I’m tempted to just save the money and spend it on a new drive shaft instead of axles. And rebuild the rear end down the road when I max out its potential.
Do my axles really look that bad..?
I’m not going to be drag racing or launch the car hard...plus I won’t be making crazy power anyways.

 

[dank GN]

Truthfully I would send it to someone that knows how to build diffs . I did mine and it took me abunch of times pulling it in and out to get the correct spacing. And if you haven’t figured out the clutches for the stock rebuild are stupid expensive you can get a whole new diff for the price of the clutches . I installed a true-trac with moser axles . And while I was there I did a set of c clip eliminators and a TA cover .

 

[dank GN]

Axles are fairly cheap I believe I paid 150ish for my set and since I was upgrading my diff i ordered 30 spline axles . The true-trac was like $450 . And the cheapest I found the correct clutches for a proper stock rebuild was around 300-350 which I think is insane imo

 

[Pronto]

Moser or Strange stock replacement axles are all you need. Just order them with the studs installed to save time. Get new bearings and seals too.

 

[Sherif]

I just got the "s" clip in the mail today. I will install it after work when I get out to the garage. I have no intentions of rebuilding or upgrading my posi unit as of right now only because I'm trying to stay in budget with my build. The only reason why I was going to rebuild it is because I thought I NEEDED to when i busted the 's' clip...and it can also easily be rebuilt down the road with the rear end still in the car. I checked the backlash and it was .007" which falls within spec.

As for replacing my axles..I was really hoping I didn't have to but I wont cheap out on it. I ordered timken seals...does anyone have a part number for timken axle bearings? I cant seem to find them anywhere...

Those c-clip eliminators are interesting. Probably worth checking out when its time to upgrade. How do those work anyhow?

 

[grass doctor]

Bearings/Races (LM501349 & LM501314) Timken, double check that LOL

SKF makes a repair bearing that moves it to a new spot axles if your axle is damaged FYI

 

[Sherif]

For a $40 “upgraded” s spring you’d think gbodyparts.com would send a quality spring. It looks like it was hand fabricated from a flat piece of sheet metal. Could’ve made this shit myself

 

[hensleyt]

I have 2 OEM springs one in the package. I don’t remember what I paid 15 years ago. Yes they look better than that,but I’m running a Gbody spring no issue. Today with limited costumers for our cars some of these parts especially custom parts are hand built.
And our venders are trying very hard to supply use which quality parts we want. Sometimes they don’t meet our standards.but will work as stated. That spring was a bitch to make, it’s not pretty but will work.
This spring has 60K miles on it OE.
With new bearings seals that spring you will forget about it appearance in a month.
The upgrade spring has more pressure on the clutches mine chirped the tires around the corners tell I got the friction modifier ratio right. I race my car so I tolerate a little more chirping than most will tolerate.

 

[Sherif]

Fair enough and completely understandable. I was just shocked to see that is what a $40 spring looks like when i opened the box...I mean honestly I would've tried making one myself. I'm all for supporting vendors though.

If it works...it works. I will pop it in tonight. I will also be stripping the rear end and painting it this week. I need to get my frame rolling on the ground again before the snow rolls through so I can set the body back on.

I ordered Moser 28 spline axles and the bearing/race/seals which should be here next week. And luckily the ARP studs I have will fit in the new axles.