Switching Pumpkins
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Pro
Joined: Jul 2014
Posts: 560
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From: Niagara-on-the-Lake, ON
Switching Pumpkins
I'm switching my rear end to a 3.36. Can anyone tell me whether a pumpkin from a 1975 Corvette will work on my 1966 L79?
Last edited by LuckyGuy; Aug 28, 2017 at 03:03 PM.
Instructor
Joined: Oct 2007
Posts: 131
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From: Illinois
Yes, it will interchange. you will have to locate a universal joint that has the 66 driveshaft u-joint dimensions on the driveshaft side and the larger 76 pinion yoke dimensions on the other. They are available from NAPA. Sorry, I no longer have the part # available to provide it to you. I have my original 3:73 rear end out of the car now and put in a 72 3:36 for highway driving. Reduces the RPM's at highway speeds.
Race Director
Joined: Oct 2000
Posts: 12,658
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From: Shamong, NJ
Yes, it will interchange. you will have to locate a universal joint that has the 66 driveshaft u-joint dimensions on the driveshaft side and the larger 76 pinion yoke dimensions on the other. They are available from NAPA. Sorry, I no longer have the part # available to provide it to you. I have my original 3:73 rear end out of the car now and put in a 72 3:36 for highway driving. Reduces the RPM's at highway speeds.
Le Mans Master
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From: New York New York
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I just recently did this on my 64 as it had 4:11 gears in it. I rebuilt a 76 rear and just used a conversion joint.
The precision u-joint # for your shaft is 369 and the # for the 75 rear is 354 so the conversion joint # is 353.
NAPA should be able to cross that number to theirs.
No need to change the companion flange on the rear.
Joe
The precision u-joint # for your shaft is 369 and the # for the 75 rear is 354 so the conversion joint # is 353.
NAPA should be able to cross that number to theirs.
No need to change the companion flange on the rear.
Joe
Safety Car
Joined: Nov 2001
Posts: 4,424
Likes: 619
From: northern CA
I just recently did this on my 64 as it had 4:11 gears in it. I rebuilt a 76 rear and just used a conversion joint.
The precision u-joint # for your shaft is 369 and the # for the 75 rear is 354 so the conversion joint # is 353.
NAPA should be able to cross that number to theirs.
No need to change the companion flange on the rear.
Joe
The precision u-joint # for your shaft is 369 and the # for the 75 rear is 354 so the conversion joint # is 353.
NAPA should be able to cross that number to theirs.
No need to change the companion flange on the rear.
Joe
John
