Aluminum Driveshaft

I had the infamous "vibeshaft" problem apparently common to fourth-gen F-bods. Over 80 mph the poorly-balanced steel driveshaft picks up a strong vibration. Fortunately I learned about a GM technical service bulletin through the (now defunct) F-body mailing list. I grabbed an image from a guru there (thanks, Jim!) and took it to Red McCombs Pontiac. They replaced it under warranty in two days when most folks had to wait a week or more. They also didn't give me any hassles about how you shouldn't be driving that fast and other weasely nonsense. For that I must say I was very pleased with the experience of dealing with them.

The fix is to replace it with the aluminum "propeller shaft" from the 1992 1LE Camaro. This part, unlike the steel shaft, is solid such that more mass is closer to the center of rotation and requires less force to change its speed.