Mystery Vibrations in Older Astros

[GLFarnes]

I could have made this a response to a previous post, but I felt it was important enough to start a new thread. I have just spent over fifteen hundred dollars under the 93 Astro. Brakes, u-joints, axels, bearings, Idler arms, and on and on, looking for an odd vibration that felt like a tire out of balance. It acted like a tire, but continued to get worse and worse. It was a major shake at about 15 to 20mph and smoothed out above and below that speed. It turnes out that the rear (fiberglass) springs had gotton weak and caused the rear differential to rotate up on the forward end. The yokes on the driveshaft were making metal to metal contact at certain speeds causing the vibration. You couldn't see the problem or make it occur with the van on blocks due to the springs assuming their normal position when lifted.

I hope this will help anyone with a like problem from spending so much time and money on a really frustrating problem.

The cure; four hundred dollar springs from a custom spring builder.

Jerry

[Kings-x59]

I'm absolutely sure that will help someone. The mystery rear end vibration problem is common. Thanks a lot for sharing your hard earned info.