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On my project car (71 vert) the previous owner provided a set of VBP's square tubing upper a-arms. Installed them but hear a clunking noise when I brake going forward, the again when braking going backwards. Thought it was calipers, but then saw the upper arm shifting back and forth about 1/8th inch on the rod. Less than 500 mi on the car. Thought maybe VBP messed up the bolts and so replaced the 1 1/4 bolts with 1" to see if that would allow proper torque. Torqued tight, but still doing the same thing.
Anyone seen this one before? Or have any ideas on what I can do before I toss these in the garbage and pay $800+ for a new set? Ouch.
In the pic below, you can see the 1/8" space where the cylinder on the arm is not touching the wider poly bushing.
I have the same arms on my '71 and they're very tight with zero play.. Is the long cross sectional bolt torqued?
Yes, to approx. 40 ft. lbs. Again, thought both the bolts might be too long and bottomed in the threaded ends of the pivot shaft, so put the shorter ones in but same problem.
With the 1" bolts in the ends of the pivot, they turned in easily then stopped dead, like they still bottomed out on something in the ends of the pivot shaft. Clearly not pulling the bushing in enough to pinch the a-arms and take out play. Can't imagine why this would happen.
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I have the same setup with no bumping. I would measure the depth of the hole and do some math to make sure you have the correct bolt. Its a good idea to torque those correctly and to continue checking them. You reminded me to check mine
The pic below shows the structure of the bush and upper A-Arm. There is a poly bush, but it sits on a metal sleeve and buts up against the pivot shaft. In the pic, a mirror is showing the end of the a-arm bush and pivot bolt. The red circles show where it hits the pivot shaft and also where the sleeve is flush with the bushing. That's why a quick stop on the tightening process.
Looks like these out-of-the-box a-arms have a sleeve that is about .048 too long, which is the gap between the a arm and the bushing.
So can return them, or complain to the mfg. Wait, VBP is out of business, so on my own.. Damn.
So for no good reason, have to re-pull these a arms, grind the .050 out of these spacers and reinstall.
And that involves pulling the radiator, headers, etc. to get these a-arms off. All to fix what was a new part in the box. Jeez.
Could you make a washer the right diameter and thickness fit, to make up the difference inside the end of the sleeve!?
Yup. The easiest for sure. It will be the same OD as the existing washer and ID will slide over the inner sleeve filling the 1/8" gap. Only need to do one side of the a-arm - alignment should not be affected very much. Easy to get to the pass side front bolt, and do-able on the rear bolt of the drivers side w/o pulling too many parts off.
Yup. The easiest for sure. It will be the same OD as the existing washer and ID will slide over the inner sleeve filling the 1/8" gap. Only need to do one side of the a-arm - alignment should not be affected very much. Easy to get to the pass side front bolt, and do-able on the rear bolt of the drivers side w/o pulling too many parts off.
Will attempt that today and report back. Thanks!
I see, I misunderstood! Your plan sounds like a winner....fill the gap👍
I see, I misunderstood! Your plan sounds like a winner....fill the gap👍
Realizing the only thing that can trip this up is if the poly bushing is bonded to the metal inner sleeve and won't slide inward to fill the space. Will know soon enough...
Problem solved this weekend. Fabricated two washers that go under the existing washer and bolts on one side. But the ID of the washer fits around the metal sleeve holding the poly bushing.. Had to grind and file it down to around .060 thick to fill the gap, but not put too much stress on the bushing. Did the front bolt on the pass side, and the rear on the drivers side. Drove it and all quiet now, and done in about 3.5 hours time including trip to hardware store. Posting this in case anyone out there has experienced the same issue.
VBP A-Arms Shifting
