intermittent steering wobble: things to check?

[BrokeMyCar]

Occasionally the steering wheel on my 82 SC wobbles/vibrates significantly when on the freeway. At first I thought I could correlate it to the type of paving underneath, but now I'm convinced it's more intermittent than that - and seems to occur more often when the tires are cold, and persists between changes in pavement grooming.

I'm going to take the car in for an alignment (inside tread is worn, again) but I'd greatly appreciate thoughts on other parts of the steering system I could check, for confidence.

Thanks,

Babak

[terryb]

Does it eventually go away after driving for a while? Flat spot from sitting?

If it doesn't go way, flat spot from tire lockup at AX/DE?

I had a tough to diagnose problem where due to AX/DE use, the tires (RA-1's) had worn somewhat unevenly causing a periodic vibration where the fronts would slowly cycle in and out of phase. At 70MPH to vibration would occur every 6 or 7 seconds and last for a couple seconds. Getting the tires rebalanced fixed the problem.

[Jack Olsen]

I've had the same thing happen in the past, and here's my slightly hare-brained take on it. I think it could be either a flat spot or wheel balance issue, but one that's created by a kind of harmonic effect between irregularities in both front wheels. Keep in mind that the two front wheels aren't always positioned the same way, relative to each other. In other words, if both valve stem were at the 12 o'clock position, then making more lefts than rights would throw those out of sync (or locking up one wheel, or driving up driveways and such that might raise one wheel). It goes away when the two wheels are on one position relative to each other, and then returns when they're back in the bad relative position.

Or there might be another explanation.

You could try switching the wheels left to right, or checking their balance at a local tire shop.

[BRP83SC]

I have some of the same experience; slight tire wobble on the freeways, but not all the time. Also, mine goes away after awhile and my tire tread is good.

I was told my tie rods were needing replacement so I was going to have them replacement, get an tire alignment then go from there.

Keep us posted.

[BrokeMyCar]

Thanks guys -

I caught Jack's note while waiting at the airport, and it spurred an experiment on the drive back. On the freeway I had lots of steering wheel wobble, which would fade and disappear after I made left hand turns... only to re-appear after I made right-hand ones! I reproduced this effect 5-6 times, over a 20 minute drive. Another note: after the car was parked for a couple hours I drove again for half an hour with no wobble at all.

This leads credence to the left-right harmonic possibility. Is there an easy way to identify flat-spots on tires?

Thanks,

Babak

[stlrj]

Originally Posted by BrokeMyCar

Is there an easy way to identify flat-spots on tires?

Thanks,

Babak

You could jack up that side and do a visual as you spin the wheel by hand.