Just purchased a diff for my Duster

[Foghorn leghorn]

Hi all, Just purchased a diff for my 71 Duster. The gearset that came with is 3.23 which will do fine. I was hoping to find a 3:55. Seller says it was his deceased father's stuff and isn't sure which year A body it was from, so I have to decipher the brake set up in order to buy new brake hardware. Anything look familiar? Still quite new to A bodies. I paid $600 CDN. so I think I got a fair deal. Missing the flange for the u joint, but seller says he will supply one.

 

[Vaanth]

Hi all, Just purchased a diff for my 71 Duster. The gearset that came with is 3.23 which will do fine. I was hoping to find a 3:55. Seller says it was his deceased father's stuff and isn't sure which year A body it was from, so I have to decipher the brake set up in order to buy new brake hardware. Anything look familiar? Still quite new to A bodies. I paid $600 CDN. so I think I got a fair deal. Missing the flange for the u joint, but seller says he will supply one.

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The pictured A-body rear axle has 1969 - 1972 style rear brake self adjusting hardware. All A-body 8-3/4" rear axles used the same brake shoes which are 10" x 1-3/4". The FMSI number for the brake shoes is 330.

 

[Icetech]

If that's a sure-grip (can't see from the pic) you got a smokin deal... a 3.23 suregrip here goes for 900-1200 now.. just for the pig...

P.S. Plus it's a 742 housing which is considered the strongest setup.. although they are all plenty strong for most people.

 

[doug 371]

Nice score Gary. That's a great price!

 

[1MeanA]

I've seen guys ask more than that just for an A body diff housing.

 

[33IMP]

Yeah, you sure didn't get hurt. Good score.

Ask if he has drums. (Hard to find).

 

[Foghorn leghorn]

Thanks for all the replies! Yes it's a sure grip. Drums were long gone. Finding somebody to replace the seals and bearings might be a challenge in Regina. So far, no luck. Was pretty sure it was a deal.

 

[33IMP]

For what you saved.on that rear, go to harbor freight, buy a press, and do em yourself!

 

[Icetech]

Are the bearings actually bad? I would trust the originals if they are in good shape and can be cleaned up

 

[MopaR&D]

If the axle bearings don't have any visible damage or wear just clean them up and regrease. The original tapered-roller style is over-engineered (like the rest of the drivetrain) and rarely fails unless abused or badly neglected.

 

[RustyRatRod]

Nice score!

 

[Foghorn leghorn]

It was all kept inside and the bearings don't look terrible. I will inspect them. Another question: He had several other complete "pumpkins". 2 were around 3:91 (don't remember the exact gear ratio he said) should I offer to buy one? I thought it might be too extreme for a street car set up, but they would be a bargain. I have hearing aids and would have difficulty hearing if the bearings are bad but I certainly can visually inspect them. A previous car, a 1968 Buick Wildcat needed the bearings in the posi replaced and I only heard it whine when I drove it with the interior gutted.

 

[Icetech]

It was all kept inside and the bearings don't look terrible. I will inspect them. Another question: He had several other complete "pumpkins". 2 were around 3:91 (don't remember the exact gear ratio he said) should I offer to buy one? I thought it might be too extreme for a street car set up, but they would be a bargain

If they are cheap buy them all that are suregrips.. they go for 800+ all the time.. USD

 

[Icetech]

BTW.. i ran 3.91s for 8 years in my challenger, 3.91 isn't bad but i had 30" tires.. great for around town but highway sucks. I have 4.30s now and it's getting annoying now

 

[Foghorn leghorn]

BTW.. i ran 3.91s for 8 years in my challenger, 3.91 isn't bad but i had 30" tires.. great for around town but highway sucks. I have 4.30s now and it's getting annoying now

I will see what he want wants for them. I won't be running 30" rubber though.

 

[33IMP]

Agree completely with #13 and 14!
I've got 28" tires and 3.91s. I can drive it on the freeway, but I tend to camp in the slow lane. Around town, it's a beast!
For a work commute, it's more than a bit much. For a five mile trip for a burger and fries, it's killer.

 

[1MeanA]

As a young guy i would look down on 3.23s but they are a good all around gear. I consider 3.55s the most gear you would want for freeway driving with stock tire height.

 

[65TerrorCuda]

3.91's and 24.5 tire, no way I'm getting on the freeway now. Short trips and tire hop if I'm not careful

 

[missing linc]

I sold a bare 8 3/4 housing for an a body last year for $500 cad. You got a great deal on that and I would grab any other sure grip carriers you can get cheap.
I ran 3.23 gears and was very happy with them.

 

[cosgig]

If the distribution block for the brake lines is almost on the hump, it is a pre-1970 unit. If the block is down on the drivers side axle tube, it is the 70 and later unit. Post a close up picture of the block here and I’ll tell you which unit you have. For brake line ordering.

 

[Foghorn leghorn]

If the distribution block for the brake lines is almost on the hump, it is a pre-1970 unit. If the block is down on the drivers side axle tube, it is the 70 and later unit. Post a close up picture of the block here and I’ll tell you which unit you have. For brake line ordering.

Here it is. There's no rust at all. under the dust is black shiny paint. This was in his dad's Dart I think he said. I generally make my own brake lines anyway.

 

[RustyRatRod]

The 3.23 is a great gear. I think the 3.55 is the gayest gear on the planet. The 3.55 is too much gear for a lot of highway driving and it's not enough for a performance car for the track. The 3.23 can actually do both respectably as long as you have enough horsepower. I'd skip right over the 3.55 every time and if If I bought a rear axle with a 3.55, I'd change it for something else.

 

[Foghorn leghorn]

The 3.23 is a great gear. I think the 3.55 is the gayest gear on the planet. The 3.55 is too much gear for a lot of highway driving and it's not enough for a performance car for the track. The 3.23 can actually do both respectably as long as you have enough horsepower. I'd skip right over the 3.55 every time and if If I bought a rear axle with a 3.55, I'd change it for something else.

I did send him a message inquiring about the 3:91 just to have it but plan to use the 3:23.
I will re do the engine.Currently has a 360 with an intake, 4 bbl and a cam in it from the previous owner. Former 6 cyl car. Have a 727 to rebuild for it as well.

 

[RustyRatRod]

I did send him a message inquiring about the 3:91 just to have it but plan to use the 3:23.
I will re do the engine.Currently has an intake, 4 bbl and a cam in it from the previous owner. Former 6 cyl car. Have a 727 to rebuild for it as well.

Yeah, the 3.91 ...or the 3.73 since they are available now, I believe would be my jump up from a 3.23 if I wanted some more bottom end grunt.

 

[harrisonm]

I agree with @Icetech Take a real good look at those bearings before tossing them. The seals are easy to replace, and you will need to do them. If you put it together with the old bearings, after determining they were OK, you really haven't lost much. The axles are pretty easy to remove.