Death to the death wobble.

[5thhorsemann]

So I have been searching threads and trying every suggestion and idea to get rid of the front end shimmy on my 73 240Z, and all I have managed to do is move the speed range at which the steering wheel vibration comes and goes. So last night a friend and I went after the problem with a vengeance.

We first took the rotors and wheels off the front and put them on the road force balancer he uses to do his race car tires. This machine is the hooptie, you can spin the tires really fast and then test the balance by applying pressure to the tire as it spins, really cool.

Front right was 1/2 oz. out by its self, and 1.25 oz out with the rotor attached. We stripped off the weights and suddenly the wheel was out by 8 oz.'s! We then match balanced the tire to the rim, and the rim to the rotor, and we were back down to a manageable 2.75 oz's which we split the weights 75/25 between the inside and outside of the rim (based on the offset) The wheel spun perfect on the machine.

We then repeated the process L/F and did just the wheels and tires on the back. It was late when we finished and I wasn’t going to do the road test with beers in my belly on a Friday night for fear Johnny Law would get his long arms into my life.

This morning we got some breakfast, went to his shop and got the car. There was almost no traffic on I-83, and I could go for it, I am proud (and amazed) to say that there is no remnant left of the shimmy all the way up past 105 MPH!!! In fact, the car is smooth as an eel, I let go of the wheel at top speed (didn’t take my hand off, just let go, I'm no idiot) and the car tracked strait and the wheel looked just like the car was sitting still.

Thanks to all for the information herein, and remember kids, there is no mechanical problem that can't be fixed, endeavor to persevere. VEVA 240Z !!!!

[Co0kieduster]

Glad to hear you got it worked it out. I plan on taking my car into the shop at my brothers school (UTI in Mooresville, nc) this weekend so we can do the exact same thing to my car. I've narrowed my wobble down, by replacing every part around the wheels themselves, to the balance.

Wish i could find a mechanic in my area that could do this for. I hate the fact that, if I want it done right, I have to do it myself instead of leaving it to the "pros."

[5thhorsemann]

Contact your local speed shop to locate a mechanic with one of the road force ballancers. Also, make sure to check your tires for roundness while they are on the balancer, 14" tires are notorious for being oblong.

[Co0kieduster]

We will have a road force balancer at the school. I put the car on jacks and spun the tires noticed a definite hop. I've heard of people shaving the tires to deal with them being out of round, or matching the high part of the tire to the low part on the rim.

There will be instructors there along with my brother so I am confident that i will be in good hands.