Bluestripe67

Anyone with the VB&P direct replacement rear composite monospring, (mine is the 330-lb) check your center mounting pads. These pads, one on top and one on the bottom capture the spring between the diff and the bottom plate. Over time/miles they might crumble, allowing the spring to rock forward and backward. With enough play this could damage the spring. I just found this exact issue with my spring mount. Called VB&P and ordered both pads w/15% discount. Dennis

Sky65

Mine were like that when I took my spring off to put the dual mount on.

kellsdad

TTT. I'm going to add some info a a few key words to make it easier for anyone searching to find this topic: vette brakes rear monospring pads

I went with the VB&P rear monospring kit when I reworked my car about sixteen years ago. When I receently noticed the rear end acting strangely, I inspected it and found all four of the polyurethane pads that help secure the rear spring missing. Further, all of the bolts securing the plates for the pads were loose. VB&P was back ordered on pads so I had a lot of time to think about what had happened. My best guess is that the adhesive that secured the pads to the metal plates had failed over time and the normal movement of the spring caused them to fall out. With the pads gone there was no tension on the bolts and they became loose.

VB&P advised that the new 2" x 2" pads are to be glued to the plates using urethane glue like that when installing windows. That left me wondering how long they would last before the glue failed. So I have tried a different approach. I purchased a 6" x 6" sheet of adhesive backed 3/16" thick polyurethane in hardness 60 from McMaster. I cut it into 2" x 3-1/2" pieces that fit over the entire surface of the metal pieces. (See photo below). That allowed me to place the mounting bolts through both the metal plates AND the pads. That should keep the pads from departing even if the adhesive fails. As a bonus, the pads grip the bolts tightly and should keep them from backing out. .... I'll keep an eye on it and report back if there is news.




VB&P rear monospring supports with pads

JohnZ

That design is doomed to failure. Adding the "pad" has converted a "hard" joint to a "soft" joint. "Hard" joints are solid, and maintain clamping force. "Soft" joints are flexible, neither achieve nor maintain proper clamping force in the joint, and result in loose fasteners.

kellsdad

JohnZ,
Thanks for the thoughts. If I can find longer bolts with the right shoulder length, I can carry them all the way through the threaded plate at the top and put a nyloc nut on top just to be sure the bolts don't back off.