Upper control arm bushings

John Burchfield

PCS Life Member
My pro car projects have been moving at a slow pace lately, but there has been progress! Saturday I picked up the '67 Crown from the front end shop where new upper bushings were installed and an alignment done. I was disappointed that there aren't polyurethane bushings available, but it sure handles and steers smoother! I drove her downtown for a tank of no-ethanol premium :D. After checking locally and finding a wide range of prices and some parts people telling me there were two sizes, I got them from Kanter Auto Products, 52.00 including shipping. The embarrasing groan from the front end on turning or braking is gone, but I still have a soft high pitched squeak somewhere up front. I've had a replacement grille for a while to complete repairs from my little bump up a while back, but I have yet to polish it to remove the oxidation. Plenty of rectangular holes to cover! This is one of those projects best done a little at a time, every day or two Hoping the distorted grille and bumper are the source of the squeak.
 

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Sometimes the source of the squeak you describe is from wore rubber coil spring mounts. Even if they look good, it may have enough of a wore spot between the coil and other parts. Sometimes you can soak the bushings (top and bottom) with WD-40 and drive it right away to see if the squeak goes away or quiets some. It will only work for a few minutes, but may help narrow down the problem.
 
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I can see where the squeak might be coming from... Look at the lower right hand corner of the picture above... the front shocks are not properly installed. The nut on the top is much too tight, and it isn't allowing the shock absorber to work properly. Another issue is that there is the wrong shock absorber upper washer on the shock. I know that this washer was supplied with the shock, and that the shock is the correct part number, however, this shock fits more than one car. The shock absorber manufacturer didn't take into consideration that there is an interference issue between the upper shock washer, and the upper control arm cross shaft.
Below are two pictures. The first one is my car with the wrong upper washer, but with the washer holding the bushing at its proper position.
The second picture is with the correct upper shock absorber washer, and showing what happens when you have the upper nut tightened too much. This is a very common error, because many mechanics believe that the rubber bushings should be under compression. This is incorrect, the shock absorber bushings should be installed with minimal compression, so the shock absorber shaft will be snug. You can also see the spot where the upper washer was rubbing on the upper control arm shaft.
The last picture shows the proper installation of the upper shock mount and comes from the Monroe parts catalog.
 

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just one of those things no one thinks of when they change the shocks. keep your old washers. if you can't find a set let me know I should still have a couple in the bucket
 
Thanks Paul! I suspected either the studs or the washers on the top of the shocks were the culprit but my mechanic didn't think so. I'll try loosening them this weekend. One fix I thought of was grinding down the washers on the control shaft side if I can't find the smaller washers. I think I came across something on the CLC website about this being a problem on late 60s Cadillacs w/ the multiple applications for the front shocks.
 
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