Steering wheel shimmy

[Diablo Dents]

Between 67 and 70 mph my steering wheel has a shimmy or flutter. Above that and below that speed it goes away. Any clue what it might be?

[tonythetarga]

Could be a few things. Tires out of balance, a bent wheel, wheel bearings, tie rod.

You could:
Have the wheels/tires balanced.
check wheel bearings for excessive play.

[Diablo Dents]

How do you check for wheel bearing play? Is it adjustable

[BeauBlues]

Balance your tires first, its cheap and will most likely fix your problem.

[scottb]

Also, check for play in your steering column. With the car parked and the wheels facing forward, grab the steering wheel and try to move it up and down and side to side. If it has play, the nylon bushing in the steering column has disintegrated. Our host sells a steel replacement that is inexpensive and easy to install.

Good luck!

[Diablo Dents]

Thanks. This is such a great source for information

[fastfredracing]

If your car sits for long periods of time, the tires may have flat spotted a little, balancing wont help much, most likely tire balance though.

[tonythetarga]

Originally posted by Diablo Dents
How do you check for wheel bearing play? Is it adjustable

Get your front wheels off the ground and grab the wheel at 3 and 9 o'clock and shake it side to side. Do the same thing at 12 and 6.
You should have some minor movement but not too much.

The bearings are adjustable but you have to take the wheel off, as well as the dust cap on the hub, which will be a bear, but there are a number of threads on how to remove that. The axle nut is what to tighten if they wheel is a bit loose, but it may also be that you need new wheel bearings and races which is a bit of a job.
If the tires are balanced and there is still a wobble, check the bearings for proper adjustment. Do a search here as there is a lot of discussion on how to, or better yet, get the 101 projects books for sale from Pelican.

[Formerly Steve Wilkinson]

I would opine that if there's movement you can actually detect by doing Tony's test, your bearings are loose. It's a hard thing to describe, since "minor movement but not too much" can mean to one person that the wheel flops back and forth a quarter-inch and to another that he or she can imagine that there's a hair's-width of movement.

If you have the slightest doubt, take off the hub dust cap--it's really no big deal and there are a variety of ways to do it (do a search) even if it hasn't moved in 100,000 miles--and then you'll see the wheel-bearing lock nut. It's actually not a nut but a horseshoe-shaped piece threaded like a nut. Loosen it by backing off the 6mm Allen screw that snugs it down and prevents it from backing off.

Then, while slowly rotating the wheel by hand, carefully tighten the "nut" by using the Allen wrench as a handle until you can just barely move the big washer under it with a screwdriver blade. You can fully tighten the locking nut and then back it off slightly until you achieve this condition, but be careful: do NOT overtighten, since that's not good for the bearing.

What "barely moving" the washer means is that if you can flop it back and forth easily with a flip of the screwdriver, that's too loose. If you can move it back and forth but need to use the wheel hub as a fulcrum for the screwdriver blade, that's too tight. You want to be able to move the washer with a firm grip on the screwdriver but without artificially adding any torque to it, like using it as a small prybar. Don't do that.

Wheel-bearing adjustment is an important DIY skill to learn. It's very easy but very valuable, since heavily stressed wheel bearings on a hard-driven car like a 911 do occasionally require a little take-up.

The alternative is to forget about 'em and replace everything--bearings and races--when they wear out, and they wear out fast when they're loose. Periodic adjustment-checking is easier; I do it several times a year.

Stephan

[rick-l]

I rebuilt the brakes (including hoses) in my 88 because there was a slight groan from the front as I took off from stoplights. A shimmy similar to what you describe went away also.