cobra valley ball joints

[Hall1836]

Is it necessary to replace the upper and lower ball joints, has anyone replaced just the lowers with success to eliminate front end shimmy/shake on the Superformance? Other than removing the wheels, do the rotors/ calibers need to be removed or loosened for clearance. Tried to call Cobra Valley but received message that the telephone number was not in service.

[jhv48]

Before you start chasing ball joints, steering rack, rotors, etc., for that 60-70 mph front end shimmy do the following: find a tire store that has the Hunter Elite Road Force Balancing machine. Then find an EXPERT that knows how to use it. Discount tire stores have the machines but rarely does anyone in the shop know how to really use it. Ask the manager if he has anyone that is an expert on the machine. If he balks, go to another shop till you find the guy that says he mounts and balances tires for race cars. Then watch him work. It’s a complicated procedure involving rotating the tire on the rim so that the high (Or thick spot) spot on the Tire corresponds to the low spot on the rim. Then the computer will tell him how to match the tire to the rim. Then it will spin the Tire and apply force to accurately cancel out any aberrations. The computer will tell him exactly where on the surface of the rim to place the weights. This procedure takes about 20 minutes per wheel so shops don’t like to do it unless you specifically ask for it. 99% of the tires they mount and balance use this same machine, but it’s only used to balance the tire. No more. And that will work on a 5000 pound SUV. But it won’t work on our light front ends.
The machine will also tell you the wheel and the tires individual runout. Rarely, you’ll get a tire or wheel that’s too far out of round for your application. Then you’ll have to get the sales shop to get another tire that is within specs.
Do this first before you do anything else. all of us with SPF’s have had this same problem.
I chased it for years, bought the new ball joints. Tightened the steering rack. Had the wheels and tires balanced on the car (that actually came closest). Checked tire pressure and alignment. Only after finding the EXPERT on the Hunter Road Force machine did I finally eliminate the shimmy.
It’s a common problem with a very specific solution.
Happy hunting.

[NRP/MN]

While Jim is 100% correct on his solution, I have been encouraging my customers to upgrade to the friction free ball joints. I just upgraded a Unique for a customer. Factory ball joints are bound up ridiculously tight and in effect add spring rate and reduced movement in the front suspension. You only need to remove the front wheels to do this. A ball joint spreader is the key. The original ball joints are 772 Chrysler screw in. It helps to have a socket for the ball joint.

[Hall1836]

nk you.

[Hall1836]

Thanks to those that responded. When I first got the car last year it had sat for several years with little or no use. I changed fluids and greased where necessary. After greasing the ball joints I noticed that the shimmy was reduced but over time returned. New tires mounted by a friend who trust. Mounted tires on the car and it felt like the shimmy improved. Yesterday, I decided to adjust the rack free play. After raising the car with the suspension fully extended, I made a jig to check the tires for run out, and adjusted the rack. I took the car for a ride and the shimmy was reduced. I thought the rack adjustment had done that. However, the longer I drove the shimmy got a little worse. My thinking elevating the car freed the suspension. I made some agressive left and rights and the shimmy was reduced but returned as I drove. I'll probably try the new ball joints and will post results. Thanks

[eschaider]

It always amazes me how some folks will ask for guidance resolving an issue and when a working solution is provided, choose to totally ignore the offering.

The solution is exactly what Jim has already identified for you. You can save yourself a lot of time and frustration finding the same solution or you can go the long route and rediscover what Jim and the rest of us have long since found to be the issue.

Of course it is always possible you could unsuccessfully search and ultimately give up never having eliminated the shimmy and instead selling the car because it is not pleasant to drive like that.


Ed

[Hall1836]

Have a nice day.

[tortuga]

But the cobra valley ball joints vs the stockers are night and day. I did mine quite a while back and don’t remember it being all that difficult, messy, but not difficult. I dont remember taking the hobs apart just the caliper off i think. Buy the tool if you decide to do them!

Steve H
1764

[tortuga]

Originally Posted by Hall1836

Is it necessary to replace the upper and lower ball joints, has anyone replaced just the lowers with success to eliminate front end shimmy/shake on the Superformance? Other than removing the wheels, do the rotors/ calibers need to be removed or loosened for clearance. Tried to call Cobra Valley but received message that the telephone number was not in service.

I think i would (i did) do both upper and lower...another thing i think the ball joints help with is bump steer?

[Hall1836]

Update on shimmy. Had the tires rebalanced on a a Hunter machine (not road force) added additional weights and not much of a difference. Then had the tires checked and balanced on the Hunter road force by a shop that has been around for years, noticeable difference but still had a shimmy over 64 MPH. Called the shop and they stated it had it had to be something other then the tires and wheels because they balanced out and wheels were fine. I was starting to believe it was the tires and wheels because each time they were done there was some difference. Went to an other recommended shop and had the tires done on the Hunter Elite Road Force, huge improvement, not a hundred percent but the best I've had. Very small vibration above 60 plus miles and will live with it. May still consider the ball joints. Thanks to Jim jhv48

[Hall1836]

SO...thought I could live with a little shimmy. NOT! After having the tires balanced five times, by three different shops all with Hunter equipment and the last three done on Hunter Elite Road Force machines, the shimmy is finally gone. I had asked repeatedly if we could break down the mounted tires and start fresh, was told that was not necessary that the machine would tell them when to dismount the tire and rotate it on the rim. Well, apparently while adding another weight the machine said no good and they had to rotate the tire on the rim to balance it! No SHIMMY!

[eschaider]

Well, well. Can ya believe that ...

Ed