I am not sure if I replied to everyone so here is the write up.

Sorry No photo's.

1. Remove the four bolts that hold the seat to the car. 15 mm socket.
( move the seat all the way back to remove the front bolts, then
move the seat all the way to the front to remove the rear bolts.)
2. Raise the rear of the seat as high as it will go. This is needed to get
to the rear # 40 torx bolt.
The torx bolts are hard to get to. I had to use a vise grip clamped to
the torx to get them loose. My torx set is for a socket ratchet.
You may be able to find the ones that look like an allen wrench.
3. Before you remove the seat move it to the middle of the track.
4. Disconnect the electrical connector. Hard to do. Took as much time
as all above.
5. Remove the seat. I placed mine upside down on a card table.
Had a piece of cardboard on the floor so not to get the top of the
seat dirty.
6. Most Important step. Make some marks with a marker on the tracks
were the two #20 torx bolts are.
I ran a line from one side to the other. Making a line on both sliding
tracks.
This will help you get the tracks back in alignment. I did not do this
on the first seat and had a lot of trouble getting them back in
were they were to start. Will bind and seat will not move.
7. Remove the two # 20 torx bolts. ( do one track at a time )
8. Remove the # 40 torx.
9. Now you can remove the screw track. Move the tracks back and
forth, it will slide out.
10. Unthread the silver block. You can also try counting turns, It will get
you close to were you began. I also wrapped some electrical tape
around the screw rod to help get back to the same spot.
You will see the destroyed rubber stops that cause the rocking and
slop in the track.
11. I used nylon washers 3 each side in each block. I put two in
front and one in back of the silver block. There still will be a little
movement but none is noticed when back in use.
Got the washers from Ace hardware. I took the whole thing down
to Ace and fitted washer till I was happy with the fit.
Size of washers are 7/16 screw 3/4 OD .440 ID. 25 cents each.
12. I also used some bearing grease to repack the block. Had that.
13. Thread the silver block back on the screw rod.
14. Slide the screw rod back in the tracks, you will have to move the tracks back and forth to get it back in place.
15. You will see it needs to go in a bushing and a little rod fits in a slot from the motor that runs the seats.
16. Your marks should line up. If not pull the whole thing out and adjust the block until it lines up. ( a real pain, but if you don't the seat will bind.)
17. Do the other side.
18. Reinstall seat.
19. Drink a beer or Crown and seven.

It took me 3 to 4 hours to complete.

Good luck, it's really not hard, just be in a good frame of mind and take your time.

 

Thanks, I have been following your fix, nice to have it all in one write-up.

 

Very nice instructions.

Suggestion: Ask a mod to include this in the permanent tech section.

 

Can anyone tell me if GM solved the rocking seat problem by a certain model year? Or does it affect all C5's throughout the entire production run?

 

Thanks to Dade01's excellent write up, I tried the fix this weekend on my passenger seat. There are a couple of things that I would like to add to hopefully make it easier for everyone else.

1. I ran a piece of masking tape from the side of bottom track over the top track and down the other side. I then cut the tape between the two tracks to assure correct realignment when finishing the job.

2. A friend told me that the reason for the rubber in the original block was to cushion the movement. If you put metal washers in instead of the nylon that Dade01 suggests, you would have a metal to metal movement that could cause the block to break.

3. I did use a torque bit that was shaped like and allen wrench to get the #40 bolt out. I could not fit a socket in. This fit right in and saved a lot of time. I got this at Auto Zone.

4. By mistake, I left the seat all of the way forward when I disconnected the power. This ended up working in my favor though, when I took the threaded shaft out it was all of the way to the end and made for much easier realignment.

Again, my thanks to Dade01, his instructions were great. I will be doing the drivers seat next week.

 

Thanks! I'll try to put this to good use.

 

Thanks for the write-up. Will keep this handy just in case I need it at a later date.

 

Thanks... Sounds like a PITA though.