Replace The Lumbar Support Hose on a GMC Typhoon
The 1992 GMC Typhoon came equipped with a set of cloth/leather embroidered seats (loved by some, hated by many) that just so happened to have a manual lumbar support bladder that you pumped up with a hand bulb and and deflated with a 1 way valve. While not the most advanced system, it does get the job done on long distance drives by adding a bit of comfort to one's lower back. The 91 GMC Syclone shares the same lumbar system. This article can be a guide for fixing a Syclone's lumbar system, however some steps may differ slightly.
- Silicone Hose
Time has been the sole enemy of the lumbar support in the 92 Typhoon seats. The hose that goes from the bulb to the bladder becomes dry and cracks or completely breaks off.
Removing the seat
This job will require you to remove the seats from the truck. The seats are bolted down to the cab via a track system. There are 4 bolts to remove in each corner of the track.
Passenger Seat Hose Replacement
You will need to separate the bottom of the seat from the back. Using a torx 50 and 1/2" remove the 2 torx screws on either side of the seats.
When you turn the back section of the seat over, there is a clip that runs down the entire length of the seat. Remove the clip to open the bottom side.
With the clip off, you can now pull open the seat and expose the bladder valve with hose connection.
Remove the old hose. Insert the new hose onto the bladder valve and begin to route it as it was originally sitting in the seat.
To get the new silicone line through the seat, you will need to turn the seat bottom over and unbolt 1 of the rails as well as undo the clips that hold the fabric to the frame of the seat.
After you get this side rail off, you will need to undo this staple. You will need a 1/2" socket to get the rail off. BE CAREFUL! make sure not to hit the lever that makes the seat slide. You WILL hurt your hand because it will fly back at you!
As you pull the fabric, pull the new line through to the proper length you need. Trim any excess off the silicone line.
Reassemble passenger seat and bolt back into truck.
Driver Seat Hose Replacement
Follow the same steps as the passenger seat to remove the bottom of the seat from the back of the seat.
Follow the same steps as the passenger seat to open the back of the seat to remove the old hose and reroute the new hose.
For the driver side, in order to get the seat track off, you need to remove 1 spring and ALL of the clips that hold the seat down on that side
The 1/2" bolt that was hidden by the track should be now visible.
Remove the clips to pull the silicone line through the fabric.
In the same manner as the passenger seat, reroute the new hose into the fabric and trim it at the proper length needed.
Reassemble driver seat and bolt back into truck.
Hat tip to SyTy.net member 2500avalanche for the original writeup and pictures on syty.net