Upper Control Arm Offset Shafts
Thread Starter
Burning Brakes
Joined: Apr 2003
Posts: 844
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From: Central KY
Upper Control Arm Offset Shafts
Folks,
I just got the Feb '05 Corvette Fever and on pp. 65-66 they talk abou using these shafts (from CC) if you can't get proper caster and camber settings. This was my problem on the right side. They got it close but not exact. Of course, I bought rebuilt arms from Van Steel (through CC) and installed them before I found all this out... How hard is it to install offset shafts now? Must I rip it all apart or can I get those shafts in without taking the UCA's out of the car? I would figure on having to unbolt them and support it all with a jack stand under the LCA. Anybody done this? I wonder what Van Steel would charge me to swap my arms out for a set with the offset shafts? As I am sure that my rear bushings are shot, I plan to send them my rear trailing arms for a rebuild after I return to CONUS. Perhaps they could do it all for me? Any thoughts?
Thanks!
I just got the Feb '05 Corvette Fever and on pp. 65-66 they talk abou using these shafts (from CC) if you can't get proper caster and camber settings. This was my problem on the right side. They got it close but not exact. Of course, I bought rebuilt arms from Van Steel (through CC) and installed them before I found all this out... How hard is it to install offset shafts now? Must I rip it all apart or can I get those shafts in without taking the UCA's out of the car? I would figure on having to unbolt them and support it all with a jack stand under the LCA. Anybody done this? I wonder what Van Steel would charge me to swap my arms out for a set with the offset shafts? As I am sure that my rear bushings are shot, I plan to send them my rear trailing arms for a rebuild after I return to CONUS. Perhaps they could do it all for me? Any thoughts?
Thanks!
Race Director
Joined: Dec 1999
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The uca has to come off but it's pretty easy to do, all you have to do is jack up the wheel under the lower control arm or balljoint to keep weight on that side so the spring doesn't jump out. Then just loosen the castle nut of the upper ball joint and pull the control arm up, then undo the 2 nuts on the cross shaft studs and you can pull it out. Then it's pretty easy to replace the cross shaft if you have poly bushings, if you have rubber you have to press them out again.
Thread Starter
Burning Brakes
Joined: Apr 2003
Posts: 844
Likes: 0
From: Central KY
CC Part Numbers
Thanks TwinTurbo! I found these parts on CC's web site:
572016 $37.75 for the kit (does it do both sides or just one?). Are they just bushings that have the shaft offset inside, or is it actually a shaft that has offset built in? Seems like a fair price if it is the shaft itself... Anyone used this kit and does it work?
572016 $37.75 for the kit (does it do both sides or just one?). Are they just bushings that have the shaft offset inside, or is it actually a shaft that has offset built in? Seems like a fair price if it is the shaft itself... Anyone used this kit and does it work?
Last edited by djcwardog; Jan 9, 2005 at 03:42 PM.
Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
I run offset cross shafts so I don't have to run shims. At the same time I redrilled my holes an extra 1/4 inch to the rear to increase caster.
I would have trouble changing the cross shafts in the car but on the bench with poly bushings it only takes a few minutes. The one sleeve needs to be pushed out, not both.
Both end bolts, both bushings and ONE sleeve must come out to change a cross shaft.
I slightly modified my inner fender so the upper A arm comes out easily through the fender. It requires a sligh cutting of the corner of the fender beside the A arm cutout. Just a little cut, repaint the cut surface and you can not tell but it makes removeing the A arm easy.
Yes a jack under the lower A arm keeps everything in place but you must seperate the ball joint. Do this with the weight of the spring pushing down on the joint and the castle nut just backed off slightly.
I did many many cross shaft switches last winter aligning the car. Rather then use shims I just kept changing cross shafts with different offsets.
I would have trouble changing the cross shafts in the car but on the bench with poly bushings it only takes a few minutes. The one sleeve needs to be pushed out, not both.
Both end bolts, both bushings and ONE sleeve must come out to change a cross shaft.
I slightly modified my inner fender so the upper A arm comes out easily through the fender. It requires a sligh cutting of the corner of the fender beside the A arm cutout. Just a little cut, repaint the cut surface and you can not tell but it makes removeing the A arm easy.
Yes a jack under the lower A arm keeps everything in place but you must seperate the ball joint. Do this with the weight of the spring pushing down on the joint and the castle nut just backed off slightly.
I did many many cross shaft switches last winter aligning the car. Rather then use shims I just kept changing cross shafts with different offsets.
Drifting
Joined: Oct 2003
Posts: 1,426
Likes: 1
From: VetteMOD
St. Jude Donor '05-'07
Norval,
Thanks for the pictures. Wow have I been confused, I always thought that offset shafts were offset along their axis in order to move the upper control arm back and increase caster. I guess thats why you redrilled the holes.
Modern cars seem to run a couple more degrees of caster than C3's are capable of. Seems like you could move the upper control arm back 1/4 inch and the lower forward 1/4 inch and get about 3 degrees more?
Thanks for the pictures. Wow have I been confused, I always thought that offset shafts were offset along their axis in order to move the upper control arm back and increase caster. I guess thats why you redrilled the holes.
Modern cars seem to run a couple more degrees of caster than C3's are capable of. Seems like you could move the upper control arm back 1/4 inch and the lower forward 1/4 inch and get about 3 degrees more?
The ORIGINAL and bestest
Joined: Oct 2000
Posts: 10,009
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From: Toronto Ontario
Toronto Events Coordinator
Norval, are there multiple offset cross shafts available all with different anounts of offset? Do you have any part #'s?
Also, when you drilled your shafts for more caster,did you fill the hole in after, or did you machine some kind of bushing to fit in the old hole?
Also, when you drilled your shafts for more caster,did you fill the hole in after, or did you machine some kind of bushing to fit in the old hole?
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Race Director
Joined: Nov 2000
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From: Waterloo ontario Canada
Originally Posted by 7t2vette
Norval, are there multiple offset cross shafts available all with different anounts of offset? Do you have any part #'s?
Also, when you drilled your shafts for more caster,did you fill the hole in after, or did you machine some kind of bushing to fit in the old hole?
Also, when you drilled your shafts for more caster,did you fill the hole in after, or did you machine some kind of bushing to fit in the old hole?
As for drilling the holes I actually put the stock crosshaft in the mill and take a milling cutter and elongade the hole 1/4 inch in the direction I want it to move. Takes only a few minutes and I get about 5 degrees caster without shims. I do take a round slug, cut it in half and put the 1/2 in the unused part of the slot and use a washer and the nut to hold it in place. With the custom cross shafts I just drill the holes 1/4 inch further forward then stock to move the A arm back and increase caster.
Offset cross shafts are meant for sagging frames to bring camber back into specs.
If you ever replace the cross shafts get someone to mill the holes 1/4 inch and it will make a big difference to caster and take less then 5 minutes.
I do them without removeing them from the a arm.
