69 GS 12 bolt - Finally getting posi installed

I have the original 12 bolt rear in my Canadian built 69 GS. Ratio is 3.08 I'm not changing the ring and pinion.

Is this the correct posi unit from the Eaton 12 bolt selection for my rear? Not sure how many splines my rear has and neither is the shop unless they tear it apart to look and count which I'm not paying them twice to tear it apart.


https://www.summitracing.com/parts/etn-19554-010

They said my pinion seal is leaking too. I also should probably have some sort of rear end kit for this right? Like with bearings and seals? They said they have loads of shims so I don;t need them but what all will I need in the hardware department? Should I just buy a ring and pinion installation kit anyway just in case?

https://www.summitracing.com/parts/rmg-8310191/make/buick/model/gs-400/year/1969

Let me know if I'm on the right track.

I'm sort of excited. All I've ever been is traction impaired.

 

That is the correct bearing kit,and you want a 3-series posi unit,30-spline axle.

 

Thanks guys! Larry is that Monzas' web page you posted?

 

Thanks Larry - Left Jim a voicemail. Wish I knew how to invite him to this thread. There's only 1 GM 12 bolt 3 series posi left in stock# Summit. Yesterday there was 3!

 

Thanks Larry - He messaged me and he did offer a Yukon Dura Grip. I'm just not sure if it is a clutch type or a locker. For my application I'm thinking a clutch type is best. Just waiting on some further details on that.

 

Thanks Larry! I spoke with Jim (Monzaz) and he hooked me up! Can't wait till this is done. Pretty excited.

 

The Yukon is a copy of the Eaton. They all have a polycarbonate clutch. It will be fine for a street car.

 

Yukon actually IMPROVED on the case after they first came out and EATON had to play catch up...lol. cases are now thicker than they use to be when Chevy was using them back in the day and Eaton aftermarket.
Eaton aftermarket also went through a powder metal spider gear phase where all the spiders blew up there for a bit...BOY did they loose the Eaton style business to Randys then....
THEY also bought out Detroit Locker company with the true trac back then and they jacked the prices to the moon. That is when Randys (AKA YUKON ) decided to copy the EATON unit as the patent ran out on the unit .

JIm
JD

 

I remember the original “Yukon” that were the Eaton cases with the numbers machines off,and they put their guts in them. That was close to 20 years ago.

 

Ken - Do you trust the shop? It may be worthwhile to have Jim or Brian (depending on who is closest) do the work if you're not sure.

 

Its about time!!

 

Will he get the correct blue pinion seal in that kit ?

 

??? Who knows these days.
I replace red with the blue them in my kits. (remember do not go by COLOR alone...MEASURE the depth.