I got into our 1996 Pontiac Trans sport for a quick errand. As I reached back over my head to pull up the headrest, there was a* behind me and the entire seatback collapsed backwards, completely flat back onto the seat behind. Fortunately I was still idling in the driveway at the time. My own investigation showed that the manual seatback recliner mechanism has _one_ bolt supporting the seatback angle, and that bolt (roughly 5/16" diameter, but metric) had sheared in two. (these are GM front-seat minivan bucket seats with a flip-down armrest on the inboard side and a large black plastic adjustment knob below it that you turn forwards or backwards to adjust or recline the seat back.) nothing else besides that one bolt holds up the seatback; when it breaks, you immediately fall over backwards. I spent the morning removing the driver's seat and unscrewing the broken stub of the bolt from inside the seat base frame. I have a collection of metric machine bolts from previous cars and found a used replacement that was a perfect fit, and everything is back together for now. I believe I have put in a bolt of the right strength. The sheared-off bolt has the following on its head, like this: 9. D (yes, a letter D, not a zero.) the bolt I put in reads "9.8" I have kept the sheared-off bolt (both halves) for inspection by any interested party. I don't believe I've overstressed the seatback (I weigh about 225 pounds, my wife weighs about 150, and no one else drives the van), and to our knowledge the vehicle has never been in an accident. I did visit a local Pontiac dealer in mchenry, il (not the selling dealer) and was able to sit down with a mechanic and review their recall database for 1996 Trans sports, but found no mention of a collapsing seatback problem. Given the location of the problem bolt within the seat, I doubt it would be unique to Pontiac only, but would be shared by all GM minivans of that year which used manual-reclining bucket seats.

- Mchenry, IL, USA

Front bucket seats collapsed upon impact.

- Stanwood, MI, USA