Steering wheel wobble

benex · July 30, 2004

I have a 99 Silverado Z71. I can feel a shimmy in the steering wheel when driving above 45 mph. Upon inspection, the wheel hubs, ball joints, tie rods, pitman arm and idler arm all seemed tight. I also swapped the front and rear tires with no effect.

I can however rotate the intermediate steering shaft a few degrees before the pitman arm starts to rotate. The Helms manual shows a lash adjuster nut in the exploded view of the gearbox (my power steering gear is the 670 gear), but I can’t find any procedure on how to adjust it.

My question is can I adjust the backlash in the gearbox, and what is the proper procedure?

Wingnut · July 30, 2004

Just curious, but when is the last time you had your tires balanced?

commanche1 · August 2, 2004

check your balance on tires and your shocks. oem shocks dont last to long . if you have 35,000 on your shocks, get them out.also alignment should be checked.

OUMike · August 2, 2004

oem shocks dont last to long ..

175k on mine and rides smooth as a babys behind

commanche1 · August 2, 2004

oumike, thats funny.

OUMike · August 2, 2004

Haha, yea I know it. Well I was reading your last post about how to tell if a shock is worn. I don't believe mine do that, but I'll check in the morning. Ya see, I really have no idea weather or not they've been changed or not. I'm the 3rd owner and the previous owner was my step father. I really don't know how current they are.

benex · August 5, 2004

How much rotational play do you guys have if you grab the intermediate steering shaft when the truck is on the ground? Could someone please do a quick check?

awdvkd · August 5, 2004

Your steering would cause your vehicle to wander not shimmy, a shimmy is usually caused by something out of round or balance. I really don't see shocks causing it either. If bad enough they might cause excessive up and down travel but not side to side shimmy. If your rotors are warped bad enough that can cause it, but they would have to be really bad to shimmy without applying the brakes. If your tires are bad enough you could have a bad tire on the front and back (sounds like Uniroyal) and that may be why it didn't stop when rotated. Good luck, vibrations can be a real pass in the a**.

benex · August 6, 2004

Just curious, what's the deal with Uniroyal?

HotdogMB · May 10, 2007

I have the same problem with my 2005 GMC seirra ext cab 4x4 Z71. The wheel wobbles when I go over a ruff surface on the road. Is there a steering stablizer on this truck, like on my Blazer?? It was doing the same thing and that's what it turned out to be. My dealer sayes that I'm crazy because they couldn't feel it. The wooble wasn't there until the dealer did a front to rear tire rotation. But they swear it's not a tire. Please help me out and prove to the dealer that I'm not crazy!! Well atleast not about this. Thanks:

Rob W

jaybyrd · May 11, 2007

This might sound crazy but it happened to me once. Side to side shimmy and got alignment, front end checked out, tires rotated, still had the issue. Dealer recommended I change the tires, then by chance I noticed what I thought was a rock stuck in the tread but it was a 4 inch spike with the end flattened down throwing out the balance...... Can never hurt to check.

Rosedog · January 29, 2008

This might sound crazy but it happened to me once. Side to side shimmy and got alignment, front end checked out, tires rotated, still had the issue. Dealer recommended I change the tires, then by chance I noticed what I thought was a rock stuck in the tread but it was a 4 inch spike with the end flattened down throwing out the balance...... Can never hurt to check.

Was that the problem? Did fixing that correct your steering wheel wobble/shimmy?

This is happening to me too. Its really becoming annoying. I checked the pressure and made it the same all around.

I guess my next stop is the Tire Shop (Les Schwab) to have my tires checked, rotated and balanced. Whats really strange about this is that it just started happening a few months ago.

It happens in the 40+mph range. If I take my hands off the wheel its left/right/left/right/left/right, nothing extreme just wobbling/shimming.

pm26 · January 29, 2008

Are you sure the dealer is balancing the tires properly? I cannot tell you how many times I had tires balanced wrong on various vehicle by stupid and incompetent chain tire store, and also car dealer employees who incorrectly mounted them on the balancing machine. All zeros on the spin balancing machine mean nothing if the wheel is not properly centered. if you ask the technician to remove the wheel from the balancer and then remount it and respin it, and if it still shows zeros, then you have some confidence that the balance if right (assuming the machine is properly calibrated of course)Also, some wheels are not hub centric, so special lug adapters may be required. Assuming the wheels are properly balanced, the tires could be out of round. This will cause vibration at speed, much like an unbalanced tire. You need to have the wheels road force tested on a machine such as the Hunter 9700 model.

My coworker has a Dodge Durango with factory 31X10.5R15 tires and he had a very annoying vibration problem. He took it to the local Dodge dealer and they balanced the wheels twice and totally wrong both times. Finally, we took the vehicle to a place that had a well calibrated Hunter 9700 machine and two wheels were out by 3/4 ounce on each side! That after the second "balancing" by the Dodge dealer.

In some cases you can have a broken tire belt which may not show during tire balancing and gets worse with increasing speed and driving time. I had a set of Michelin tires on my car that did that. Even road force measurements were within spec.

Improper alignment will generally not cause wheel shimmy or vibration. Worn out shocks may cause wheel hop on uneven road surface in extreme cases which can be perceived as vibration, but again, that would be rare.

unit731 · January 29, 2008

I have had similiar problems in various vehicles.

If all above has been checked and done, it boils down to tires. I have had bad tires balanced and rebalanced. I did have one bad rim once.

You need to get the owner/manager of tire place or a senior mechanic to do the balance. You need someone who knows tires.

Could be belt separation or tire out of round. They will balance a tire til the cows come home and not solve the problem.

hubbycap · January 30, 2008

The only operation that could isolate the known variables to exclude tire/wheel assemblies would be to swap a single front to a single rear position. Test drive and if shimmy still present, do a full front to rear swap. You may have two bad tires and one may currently be on the front and one on the back. This would determin this in at most, two steps.