toms 12bolt question/problem?
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Joined: Mar 2002
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From: Ashburn VA
toms 12bolt question/problem?
I have something binding up in my rear of my vette. I took out the halfshafts and the Ujoints(1480's) looked/moved fine. I bleed my brakes and drove it around the block and that wasn't it, the brakes had no heat in them indicating a sticking caliper. When the car is in neutral I can't move it on a flat surface. The rear is a toms 12bolt with a 5.13 gear. What in the world would bind the rear up like this? I checked the fluid, looks/smells fine. The car binds then lets loose, binds then lets loose when driving. Im stumped as to what would be causing this, if the posi is broke I would imagine it just would have no posi. Anybody have any idea's?
Thanks
J
Thanks
J
Melting Slicks
Joined: Feb 2004
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From: largo florida
It could be part of a broken spider tooth or something floating around and temporarily getting stuck between the gears. I believe GSC3 had this problem with his old setup. It would drive fine, then all of a sudden the rear would lock for a split second then go back to normal.
Le Mans Master
Joined: Nov 2004
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St. Jude Donor '07
did u set up the pinion right? i grenaded a rear end in my old work that we were doing full throttle donuts in and it did that and i broke spider gears so i think its the spider gears also.
Melting Slicks
Joined: May 2001
Posts: 2,131
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From: May help you? You can sure as hell try!
Did you add the GM positraction lube additive? I think one is recommended but Bair's suggested two. I've also heard that there really is no substitute for the additive as others tend to cause problems. Don't know what Tom's recommends but 12 bolts should be no different than the standard Corvette in this regard.
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Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
You need to break it down as to where the problem is: I'd unhook the half shafts at the spindle end by removing the 1/2 the U-joint.
If it rolls and binds that could be as simple as warped rotor. I had one so warped that you could hear it every rotation of the tire without applying the brakes. Up on jacks I could rotate the tire with my hand 1/2 of a rotation and then it wouldn't budge. You also have all the bearings and spindle on the trailing arm.
I've had broken Posi cases and it would still go around - they just make allot of noise.
I also destroyed my first Vette rear end. The case was eaten away on the outside from the yokes grinding on it. when the stock yokes get ground shorter than the snap ring they have so much play the outer yoke end grinds on the case.
I just threw it in the dumpster and bought all good stuff with a 4.11 and custom yokes...... Lot's of tom's parts.
If it rolls and binds that could be as simple as warped rotor. I had one so warped that you could hear it every rotation of the tire without applying the brakes. Up on jacks I could rotate the tire with my hand 1/2 of a rotation and then it wouldn't budge. You also have all the bearings and spindle on the trailing arm.
I've had broken Posi cases and it would still go around - they just make allot of noise.
I also destroyed my first Vette rear end. The case was eaten away on the outside from the yokes grinding on it. when the stock yokes get ground shorter than the snap ring they have so much play the outer yoke end grinds on the case.
I just threw it in the dumpster and bought all good stuff with a 4.11 and custom yokes...... Lot's of tom's parts.
Tech Contributor
Joined: Aug 1999
Posts: 15,195
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From: Connecticut, USA
Originally Posted by BADDD
Yes, I can't move it by hand. I can move it with a long pry bar and some old bolts in the axle shafts.
I would drop it out and open it up for a look. Let me know what you find and post some pictures if you can.
good luck,
Gary
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Joined: Mar 2002
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From: Ashburn VA
The rear is not a new rebuild, Iv driven 500 miles or so since I got the car and now its just starting to bind up. Something must have let loose, and I dont know of anything else except the spyder gears that could maybe cause this, broken/chipped ring or pinon gear maybe? Its not a clunk kity cluck sound, just every revolution it feels like something is binding up.
Thread Starter
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Joined: Mar 2002
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From: Ashburn VA
Yes the picture is the same rear. The bearings and rotors spin with out binding up with the halfshafts out. I think gtr1999 is right, i am just gonna have to pull the rear and open it up. Anyone have a 3.90 12bolt gear and posi set-up they want to sell?
Thanks
J
Thanks
J
Le Mans Master
Joined: Oct 2002
Posts: 5,714
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From: Silver City NM
St. Jude Donor '05-'07
Originally Posted by BADDD
Luckly I didn't pay the $2450. I really doubt if my 350 could do this with street tires. maybe it was already on its way south.
Dep
to that.
