Need help here. My '70 442 has a '71-'72 10 bolt olds posi (coded SS). When I got the car the axle had no pinion side gears or center pin. I put the side gears and center pin from a '70-up chevy 10 bolt posi in but while the center pin fits great the side gears have quite a bit of play in there. Anybody know where I can get parts or if I can shim this?????

 

I don't know about shimming but I have the 10 bolt internals you need from a 72 10 bolt

 

I have any and all.
It sounds like you might just need the thrust washers for the smaller spider gears,or if it is a posi,the clutches need shimmed tigheter,to take up the play in the spider gears.
The SS-code is a 3:23 posi,for 71-72. Is that what you have?

 

Yes it's a 3:23 posi. Are the side gears (smaller ones) the same as in an open diff? Like I said the gears out of the Chevy posi fit and I do have the thin curved washers behind them but there is an 1/8 to 3/16 gap between the gear that is at the top when installed (I assume because of gravity)and the case of the unit. Shimming the clutches had not occurred to me (I'm a painter) as the posi unit works but it's not real stiff when you turn one tire against the other. I did not take the s spring out to check the condition of the clutches but will have to when I decide to put axle seals in. It just seems like a lot of play in there as well. I don't know if its considered unsafe and I sure don't want to risk a new frame off resto on it.

 

If the Chevy rear is another 8.5",then the spider gears will swap. The 8.2" are different. What is the Chevy rear out of?
I can send you a pair of
8.5" spider gears & thrust washers,if you want to be sure.

 

Out of a '70 impala. That's the 8.5 rear by what I know. It's a 3:42 posi if it matters.

 

That's an 8.5 rear. Only the a-body rears were 8.2 until '72.

 

Does the Impala posi have the 4 coil springs for the clutch packs,or the single "S" spring?
They started the 8.5" 10-bolt in 1971,for the Cutlass/442,and the Skylark/GS. Other cars like the Camaro & Firebird followed suit. The Chevelle & Monte kept the 8.2" 10-bolt and the 12-bolt chevy.The lemans/GTO kept the 8.2" BOP 10-bolt.

 

It's the s spring posi. It is an 8.5 unit 3 series carrier. How much can you shim these to take up the clearance I'm describing?

 

I've added anywhere from .020" to .070" of shims to the clutch pack.I achieve little or zero play in the spider gears.

 

Well sweeet! Looks like I'll be ordering a shim kit from SU. Thanks for the advice! This rear will get me by until the original 12(ish) bolt is back in the car.

 

Is the posi unit from the 71 3:23 have casting number 725 on it?
Does the one from the Chevy have casting number 410408N on it?

 

Yes the Chevy posi has that casting. I will have to take the cover off to be share of the one in the car but I'm share your right. That rear still had the gm ring and pinion which is how I got the ratio. and has no c clips and took the olds gasket.

 

What are your plans for the Olds 10-bolt after you reinstall the correct 12-bolt?

Thanks,
Anthony

 

Shure not share. That will teach me to post from my P.O.C. droid phone. It's correcting me! Incorrectly! Well seriously it will be a while before the 12 is back in the car. It needs everything including a posi and some other parts I don't have. Will keep you in mind if your interested as I'm not much of a hoarder.

 

Thanks and good luck with the 442. Anthony