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I am replacing the lumbar bladder on my C7 competition driver seat because it leaks and only lasts about 5 minutes. I found the replacement part and have it with me. I have the seat apart down to removing the bladder and bladder frame assembly. However, the bladder frame is attached to the seat with a fastener I've never seen. It appears to be some type of rivet or special fastener. Any knowledge/experience (not guesses) what this is and where to get 4? Or should I figure out a replacement fastener?
I added a penny for size reference in the first pic.
McMaster Carr has just about every fastener known to mankind. There website is second to none. All you need to do is drill one out, measure, and search their website.
Best of luck
Last edited by Vetteman Jack; May 26, 2026 at 10:08 PM.
I looked on YouTube for a video about replacing the lumbar portion of the seat in a C7, but all I could find was a guy that goes into a lot of detail about doing the same thing to a C5. He also custom makes parts for the seat. it’s about 22 minutes long and it might be worth a watch.
according to the GM service manual there are 4 rivets that need to be drilled out to replace that bladder. (item 2 on the picture).
I could not find any part number reference for them in the shop manual. if it were me I would go to a dealer parts department and have them look them up, sometimes they have good breakdowns of parts needed like this. or you could probably get by by buying some properly sized pop rivets and using them.
Last edited by raisinjack; May 26, 2026 at 05:28 PM.
UPDATE: They were in fact large head rivets. However, there didn’t seem a reason for rivets when another type of fastener might work. I found some auto trim fasteners at the hardware store that worked great. 1.5 hours later my lumbar bladder was back in service. While the Amazon lumbar pillow was ok for a short time, it sucked in the long run.
C7 Lumbar bladder replacement
