Locking kit for differential?
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Locking kit for differential?
I bought a real POS 70 a few weeks back that I have decided to put on the road. Unfortunately, Bubba has been into everything in this car. I am dropping the entire rear suspension and differential to correct Bubba's mistakes and I noticed something odd. The stubs that come out of each side of the differential are perfectly lined up and in phase with eachother. In normal use, these are constantly changing position with respect to eachother as the car goes around turns, etc. Is it possible that someone has locked the two halves of the Positraction differential together somehow? Is there such a kit to do this, or is it likely welded together or some other crazy thing? The rear is marked on the bottom as a 1971 3.08, and it appears to be 3.08 by counting turns.
Thanks.
Fred
Thanks.
Fred
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
A mini spool would do that. Only way to know for sure what's in there is to crack it open. Or if you're real flush, get a borescope, stick it in thru the fill plug, and look.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Thanks so much for the reply. I will most likely take the cover off as it looks like they sealed it with RTV and no gasket. What is a mini spool? Is it something I can leave alone or something that should come out of there? I am certain they were racing this car, and I have no plans for that.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Pro
Joined: Sep 2002
Posts: 624
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From: Melbourne, Fla. 6 months- New Middletown, Ohio 6 months
A spool basically eliminates the spider gears in the differential and is primarily used for drag racing. It forces both wheels to pull together. A quick test would be to drive in a tight circle. If there is a spool in the car the inside wheel will be forced to turn the same number of rotations as the outer and will squeal on the pavement. If you are worried about damage to the vehicle, do it on wet pavement.
Instructor
Joined: Aug 2008
Posts: 110
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From: Baton Rouge Louisiana
Bubba may have welded the Spider gears together which makes it act like a spool. I am not sure if the vette diff will allow that (as I haven't taken it apart and looked at it) but that can be done on solid axle cars (My dad had a drag car that he did that to years ago in a 8 1/4 Mopar).
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 924
Likes: 2
From: Kearneysville West Virginia
Well, good news! I dropped the rear out of the car today and pulled the cover. It looks like a normal posi differential to me, although I have to admit, this is the first one I have seen other than pictures. I see the differential gears and the four springs in the middle that put the pressure on the clutches. It is nice and clean and no signs of tampering or welding. So, perhaps, it was just by chance that both yokes were perfectly lined up.
I have another question. Someone had installed a differential crossmember locating kit, you know, the kind you can buy from some of the Corvette supplers. It has the studs and round aluminum disks that hold the crossmember cushions up tight. Is there really an advantage to having this modification if I am not planning on all out drag racing?
I have another question. Someone had installed a differential crossmember locating kit, you know, the kind you can buy from some of the Corvette supplers. It has the studs and round aluminum disks that hold the crossmember cushions up tight. Is there really an advantage to having this modification if I am not planning on all out drag racing?
