'77 differential spec
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Joined: Apr 2005
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From: Illinois, USA
'77 differential spec
Okay, I have new side yokes to replace the worn down ones that were in the differential, but when I put the new ones in, I get about .026 and .032 end play on them. Should I be trying to take out the center pin and rotate it (since it shows a little bit of wear as well)?
Next, what is the amount of "slop" between the pinion and ring gear that is acceptable? To the best I can measure, I think I have about 1/64th or so slop (measured at the edge of the ring gear)
If it matters, this appears to be an original rear end with the optional 3.08 "highway" gear.
My reason for the disassembly was to replace a cracked cover, and I have also been trying to track down what feels like a tire vibration, but it only occurs under accelleration (I am replacing the bushing on the differential bracket, and putting in new cushions on the crossmember).
Thanks in advance for the assist.
Brian.
C3nMe.
Next, what is the amount of "slop" between the pinion and ring gear that is acceptable? To the best I can measure, I think I have about 1/64th or so slop (measured at the edge of the ring gear)
If it matters, this appears to be an original rear end with the optional 3.08 "highway" gear.
My reason for the disassembly was to replace a cracked cover, and I have also been trying to track down what feels like a tire vibration, but it only occurs under accelleration (I am replacing the bushing on the differential bracket, and putting in new cushions on the crossmember).
Thanks in advance for the assist.
Brian.
C3nMe.
Tech Contributor
Joined: Aug 1999
Posts: 15,154
Likes: 3,959
From: Connecticut, USA
Unless you tune the posi you're not going to get any less endplay out of the new yokes. The pin is not .020" undersize. The clutches need to be correctly set to get endplay down. This one reason I recommend rebuilding a diff if the yokes are worn. .020-.025 will work but it coul dbe much better.
The play in the ring gear is backlash and needs to be set in range of .005-.008" depending on the ring gear set. Original GM gears are usually about .005-.006" This is not a simple adjustment. You have to check pattern and avoiding any step in the procedure will result in failure or a noisey differential.
The play in the ring gear is backlash and needs to be set in range of .005-.008" depending on the ring gear set. Original GM gears are usually about .005-.006" This is not a simple adjustment. You have to check pattern and avoiding any step in the procedure will result in failure or a noisey differential.
