83/4" rear endcswap.

robndi43

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I have a 61 Chrysler New Yorker that i want to switch to an 8 3/4 sure grip rear end.
What car would I be looking for a donor rear end to swap the easiest into my Chrysler

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Your 61 Chrysler should have an 8 &3/4 rear from the factory. The Sure Grip option started in 1958. Do you want to swap to the non-tapered axels? If that is what you are looking to do, there are charts that list the different size housings. You should be able to find one that bolts in.
 
Why is it that everyone wants to go through all the work to swap out the tapered rear axles? If you have the correct puller, working on the rear is actually very easy. I bought one off ebay and it made rear brake work on my '58 Plymouth and '59 Dodge super easy.
 
Why is it that everyone wants to go through all the work to swap out the tapered rear axles? If you have the correct puller, working on the rear is actually very easy. I bought one off ebay and it made rear brake work on my '58 Plymouth and '59 Dodge super easy.
He probably cares more about having the sure grip than the tapered axles. Nice 61! Ya gotta love that clear steering wheel and astra dome cluster!
 
I changed mine years ago when I used to Drag Race it. It was much easier and faster to swap gears with the non-tapered axels. There is nothing wrong with the tapered axels, they work fine. You can still add a sure grip and keep the axels you have.
 
I changed mine years ago when I used to Drag Race it. It was much easier and faster to swap gears with the non-tapered axels. There is nothing wrong with the tapered axels, they work fine. You can still add a sure grip and keep the axels you have.
That I did not know. Is that true? I thought for the tapered axle rear end you have to find an early sure grip pumpkin which is damn difficult and really limits what gear ratios you have available..?
 
That I did not know. Is that true? I thought for the tapered axle rear end you have to find an early sure grip pumpkin which is damn difficult and really limits what gear ratios you have available..?
I think you can use a later sure-grip but the center spacer is 1/4" wider, so you need to shorten the axles 1/8". Emphasis on "I think you can". I've never done it, but I think I read about someone else did that. Again "I think".

If that could be done, you could buy an aftermarket sure-grip and use your existing gears etc.

Photos shamelessly stolen from a post by @413 (who may have the definitive answer)

1 1/4" center spacer used '64 and earlier. 1 1/2" for '65 and later.

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The rear gears went in my '57 about 25 years ago. The housing is from I believe ( I put it in a long time ago) from a 1964 Plymouth Belvedere. While I was waiting to get my new gears, I put a center section from a 1958 Plymouth in it. It was 3.18-1 ratio, which I thought was odd, but it fit and worked fine. I am pretty sure it would work the other way too, putting a newer center section in the older housing.
 
The rear gears went in my '57 about 25 years ago. The housing is from I believe ( I put it in a long time ago) from a 1964 Plymouth Belvedere. While I was waiting to get my new gears, I put a center section from a 1958 Plymouth in it. It was 3.18-1 ratio, which I thought was odd, but it fit and worked fine. I am pretty sure it would work the other way too, putting a newer center section in the older housing.
I'll look into it. Thank you.
 
I think you can use a later sure-grip but the center spacer is 1/4" wider, so you need to shorten the axles 1/8". Emphasis on "I think you can". I've never done it, but I think I read about someone else did that. Again "I think".

If that could be done, you could buy an aftermarket sure-grip and use your existing gears etc.

Photos shamelessly stolen from a post by @413 (who may have the definitive answer)

1 1/4" center spacer used '64 and earlier. 1 1/2" for '65 and later.

View attachment 720692
View attachment 720693
Interesting.
Thank you.
 
I think you can use a later sure-grip but the center spacer is 1/4" wider, so you need to shorten the axles 1/8". Emphasis on "I think you can". I've never done it, but I think I read about someone else did that. Again "I think".

If that could be done, you could buy an aftermarket sure-grip and use your existing gears etc.

Photos shamelessly stolen from a post by @413 (who may have the definitive answer)

1 1/4" center spacer used '64 and earlier. 1 1/2" for '65 and later.

View attachment 720692
View attachment 720693
This is correct. All sure grips are a 1.5" center spacer. Glad my photos are making the rounds, it's what they are for!
 
Was going to say the same thing. Definitely the way to go and do away with tapered axles. Makes changing center sections easier.
After making a swap, such as this, I assume the driveshaft has to change, which would result in a change to the parking brake?
 
After making a swap, such as this, I assume the driveshaft has to change, which would result in a change to the parking brake?
You should be able to use the stock driveshaft with no problem. If the new rear has the larger u-joint, you can easily get an adaptor u-joint and all will be good.

Just use the existing e-brake on the trans. No need to change.

It might be a good time to have a new shaft made with a standard u-joint at the front instead of the CV joint though. That's up to you. My '65 Barracuda has a converted shaft in it.
 
You should be able to use the stock driveshaft with no problem. If the new rear has the larger u-joint, you can easily get an adaptor u-joint and all will be good.

Just use the existing e-brake on the trans. No need to change.

It might be a good time to have a new shaft made with a standard u-joint at the front instead of the CV joint though. That's up to you. My '65 Barracuda has a converted shaft in it.

Ok. I'll look into doing that. Thanks for the information. Its appreciated.
 
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