Because I like cars, I always followed what they were doing with Corvettes over the different generations. I was never really inclined to own one, but a while back I noticed C5's were getting cheap and seemed like a lot of bang for the buck, so was tempted a time or two. In the immortal words of the late, great Bill Paxton, the Vette gets 'em wet. My son has had a series off them, the latest is this 2001 6-speed Z06. A few weeks ago, he was getting on it on an on-ramp and something let go and he was dead in the water. So we finally had some time to find out what the something was. As I researched these cars with the rear-mounted transmissions (C6 and C7's have the same set-up) I found out that a lot of the drivetrain problems they have are related to age more than miles. It's the dang torque tube for one thing, so we thought maybe it was a coupler that had let go.
So up on the lift she goes -
Here is what the torque tube looks like for those not familiar with these cars. The front end mounts to the bellhousing, the driveshaft runs through it, with the rear end bolted to the transmission which bolts to the axle.
Out of the car -
The axle is mounted to a cradle that is bolted to the back of the car. It takes a lot of disassembly to get to this point. I hear a clutch job on these cars runs $2000 plus to hire it done. I can understand why.
We found this while taking it apart. The top bolts holding the tranny to the axle were completely backed out and flopping around. Amazing they were still there. A big gap is visible. It is clear this has been apart before, and the numb nut putting it back together used the wrong bolts. They are too short, and only engaged maybe three threads. Some people shouldn't be allowed around tools.
A Tremec T56 6 speed transmission. Can anybody tell what is wrong with this picture?
So it wasn't a torque tube/driveshaft problem (dang it). The mainshaft broke at a snap ring groove right inside the case at the output end. The misalignment caused by the loose bolts at the transmission/axle junction is no doubt the culprit.
We looked everything over after pulling the case and shafts and it appears there was no other damage. No chunks on the magnets. There is some minor visible wear on syncros and gears, but what you'd expect after 87,000 miles. Everything still looks serviceable.
We will leave the main shaft assembly together until the new one comes in for what is probably an obvious reason.
We are mulling over what else we might do while it is apart. It looks like it has the major upgrades these transmissions got as time went on that I know about. He will order parts tomorrow. He is going to be spending some money for sure. Welcome to the world of high performance cars. If any of you have advice or experience to share on these transmissions, I'd appreciate hearing it. Stev-o?
