Could a sticking brake caliper cause steering wheel shimmies?

[Bmm001]

Some background:

 

1995 Subaru Legacy 138,500 miles.

 

Got my wheels balanced and an alignment performed by Subaru mid-june.

 

Got my front pads replaced and rotors resurfaced at the end of June by my independent shop.

 

I have a wobble in my steering that seems to come and go randomly as I drive. It does not seem to be related to speed. Sometimes it wobbles a lot between 30 and 40 MPH and then smoothes out randomly as speed increases. Even at highway speeds it seems to come and go. Sometimes it stops wobbling after I come to a stop at a light and then start up.

 

If I threw a wheel weight or have a bent wheel, wouldn't it wobble all the time?

 

I ask about a sticking caliper because sometimes the wobble seems to come and go after a brake application (slowing or stopping). Also, yesterday, I heard a loud click after I parked my car and got out (this was about 30 seconds after the car was parked and shut off). It did it twice yesterday in the same situation, and also this morning as I got out of the car to go into my office. Could the click be something "unsticking?" I haven't noticed a decrease in gas mileage so if something is sticking wouldn't I notice that?

 

Is it possible something in the steering/suspension is bent/out of whack? I don't hear any weird noises when driving or steering (I know what a bad wheel bearing sounds like) or clunks. I'm going to my shop today for an oil change, and want to know what types of questions to ask so they can take a look.

 

Thanks in advance,

Brian M.

[idosubaru]

caliper should definitely make a difference in gas mileage.

 

front struts, tie rod, ball joint, steering rack bushings.

 

i'd guess struts at the moment - check to see if any of them look wet, like they're leaking and loosing fluid.

[Rooster2]

my best guess is that you have a tire out of balance, or a bad tire. Prolly one of the front tires. They will do that, wobble at certain speeds, and not at other speeds. Get all four tires balanced, hope that fixes the problem.

[Bmm001]

Thanks for the input. I'll definitely have them check all those things out for me while it's up on the lift.

 

They're replacing a CV boot anyway so they will be looking at all those suspension components.

 

It's very possible I knocked something out of whack driving around the suburbs of Philly a few weeks ago--some of those roads are bad!

 

I sure hope it's not a bad tire, but the wheels were allegedly balanced properly by Subaru at the beginning of June. If all the suspension components check out as OK, I guess we'll have to consider a bad or out-of-balance tire/wheel. They don't seem to be wearing funny but I guess it's possible.

 

Brian

[McDave]

Go ahead and rotate the tires front to rear while it's on the lift. See if the problem follows.

[Bmm001]

The verdict:

 

Mechanic drove the car, felt some slight binding. Put it up on the lift and shook the drive axle... TONS of play. All the rest of the suspension components solid and tight. Replaced the axle, and it drives like it's 30,000 miles younger!

 

He said in their experience, bad outer CV Joints click, while bad inner joints (mine had a torn boot) don't make noise but show up as binding and wobble through the steering wheel.

 

I didn't realize how much free play my steering wheel had until I got in it with the new axle and was amazed at how tight and responsive the steering was again!

 

Brian

[OB99W]

[...]Put it up on the lift and shook the drive axle... TONS of play.[...]

Confirms what I said in post #6 of this thread:

http://www.ultimatesubaru.org/forum/showthread.php?t=89177

[chef_tim]

Just for kicks and grins, a sticking caliper will also cause a shimmy/shake in the steering. Tim

[OB99W]

By itself, a sticking caliper won't cause shimmy/shake in the steering. As long as the rotor is of uniform thickness and finish, and not warped, a sticking caliper's symptom will be loss of some gas mileage and perhaps some pulling.

 

If there is sufficient sticking, and it isn't noticed soon enough, that can cause the rotor to overheat, with the possible result of warpage and uneven wear. Once the rotor is in that condition, shimmy/shake are possible. However, at that point the problem will be evident any time the brakes are applied.

 

Since the original poster didn't complain of loss of gas mileage or a consistent shimmy or pulsation with brake application, a sticking caliper wouldn't be a likely cause in this case.