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Old 07-24-2017, 04:29 PM
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teamo
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Putting the rear suspension back together. The AIM diagram shows 60-90 ft lbs for the side yoke u joint caps. Does this mean that I torque it in two steps 60 then 90 or is this a range of torque and I should set it somewhere in the middle between those two numbers? 90 lbs seems pretty high to me for those size bolts.
Old 07-24-2017, 04:35 PM
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MelWff
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you might want to look at this post

https://www.corvetteforum.com/forums...fications.html
Old 07-24-2017, 04:47 PM
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BlackC3vette
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Originally Posted by teamo
Putting the rear suspension back together. The AIM diagram shows 60-90 ft lbs for the side yoke u joint caps. Does this mean that I torque it in two steps 60 then 90 or is this a range of torque and I should set it somewhere in the middle between those two numbers? 90 lbs seems pretty high to me for those size bolts.
90 foot lbs or inch lbs?
Old 07-24-2017, 06:15 PM
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DUB
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Whenever I have a range...which when GM writes it in the assembly/service manual...it is any torque from 60lbs/ft TO 90 lbs/ft is acceptable..I ALWAYS use a torque value that is in the middle...so it would be 75 lbs.ft.

And do not be surprised that you tear up/twist up a couple of the french locks when doing this.

Those bolts can take 90 lbs/ft...just make sure you do not lubricate them ...because lubricating a bolts thread..and the type of lubricant that is used DOES drastically change the torque needed to be applied. NOT my opinion on this but a fact.

http://www.engineeringtoolbox.com/to...ts-d_1693.html

DUB
Old 07-24-2017, 06:45 PM
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OldCarBum
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As stated above 60 lbs/ft - 90 lbs/ft is the torque range for the bolts and then find the middle torque of 75 lbs/ft. Torque the bolts in a specific pattern and check to determine if there is a required sequence they are to be torqued to. I will usually follow a pattern and torque all bolts in the sequence to a low torque valve. In this case I would snug all bolts, then torque all the bolts to around 30 lbs/ft, then all to about 60 lbs/ft, then to the final torque of 75 lbs/ft. Do not torque each bolt to the final torque then move on to the next bolt. Once I do the final torque I will check all bolts again at final torque to insure even torque. Yep, I'm a little OCD.
Old 07-24-2017, 06:57 PM
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teamo
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Thanks for the link and the help. I started on the half shaft to flange bolts. It was tough to get to just 60 lbs because it's tight getting the socket in that space between the u joint and the flange. Nothing is hooked up as far as driveshaft to trans so the rear differential is just spinning. I used a pry bar against the wheel studs and had to try and hold everything in place while I torqued down the bolts. I'm going to go back and get them to 75 lbs when I go back out there. Not tonight though my back is about ready to snap from hunching over under the wheel well. I'll hit it tomorrow.

Last edited by teamo; 07-24-2017 at 06:58 PM.
Old 07-24-2017, 07:09 PM
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DUB
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Teamo,
Are your rear brake calipers installed???? IF so...slide a screwdriver down in the cooling fins and have it so it will stop the assembly from moving because the screwdriver will lock against the caliper housing where your brake pads are. AND...when I torque these bolts. I get ALL of them in and tight to hold it together. Then I take out 2 bolts so the french lock can be installed. THEN I rotate the half shaft so the lowest bolt is about 5 O'clock or 5:30 and then the upper bolts is about 8:30 on the driver side if you are facing the head of these bolts.

IF you do not have the caliper ON..then I also use a pry bar like you did and that can be a challenge at times.

DUB
Old 07-25-2017, 11:43 AM
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No calipers installed yet, I still need to rebuild them. I'll keep at it with the pry bar. I installed the lug nuts on the wheel studs to keep the pry bar from damaging the threads.
Thanks

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