So need a 373 posi for a 7.5. Helping a friend with a low budget build 84 cutlass. Has a 307.

[gnvair]

Yeah, most Astro Van's are 3.23 open. The Wrecker had to open quite a few to get 3.42 gears and still open.

Yeah, most Astro Van's are 3.23 open. The Wrecker had to open quite a few to get 3.42 gears and still open.

All of the 2001 to 2005 Astro vans have either 3.42 or 3.73. No 3.23's after 2000.
The earlier ones with the 4 cylinders and 60 degree V6's almost all had 3.73's
But, Astro vans used to be a great source for 3.73's

 

[gnvair]

The hard thing is going to be finding a used 3 series 26 spline carrier. Nothing after 88 used 26 spline so that means any vehicle you find will have to be older than 88 to get a 26 spline carrier. The 88 and newer stuff (except G body) had 28 spline. You could do 28 spline but would need a pair of axles from a 84-87 GN or 442. I did this and it works, but you need to grind the end of the axle for clearance at the cross pin. It might be more beneficial to look for a
"kit" on Ebay with gears, carrier and bearings.

 

[bikerlaw]

I have a complete 4.10 posi rear end out of my '81 El Camino.
$400

 

[Drkuhar]

I just ordered the quick performance gm 7.5 kit. Posi carrier, bearing kit, ,gaskets and seals, your choice of gears (i got 3.42) for around 550. I also got the optional solid pinion spacer and shims that does away with the crush sleeve

 

[olds307 and 403]

All of the 2001 to 2005 Astro vans have either 3.42 or 3.73. No 3.23's after 2000.
The earlier ones with the 4 cylinders and 60 degree V6's almost all had 3.73's
But, Astro vans used to be a great source for 3.73's

These are the earlier 26 spline, so pre 89. Not up here apparently. I told him 3.73 would be fine, 6 of the 8 were supposedly 3.23, the other couple, 3.42. This is what he told me. I went looking for the same thing. Surprised so many were open but I owned a 94 Z71 with factory open diffs.

 

[bracketchev1221]

I did the Monte SS 3.73 rear. Got one complete and bolted it right in. I miss those days, the rear was so new it still had the drum clips on the studs.

 

[hunter_alexander]

Thanks all for the reply. Looking into options and passing the word. For those that offered what they have, Ill keep you posted.

 

[Steve 82 Elly]

I just ordered the quick performance gm 7.5 kit. Posi carrier, bearing kit, ,gaskets and seals, your choice of gears (i got 3.42) for around 550. I also got the optional solid pinion spacer and shims that does away with the crush sleeve

I was looking at these kits also, have you received it yet? What's your opinion? Does everything look & fit good? Just wondering what your thoughts are about these kits.

 

[mc1984ss]

I have a posi carrier with 3.73 gears for sale in the classified section let me know if you have any questions

 

[mc1984ss]

Auburn posi and Richmond 3.73 gears for sale

I have a auburn limited slip with Richmond 3.73 gears for sale. These were professionally installed in the rear axle I removed them from and have very low miles on them. You can see in the one picture there is a slight flaw in two of the teeth on the ring gear but appears no worse for wear. If I...

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