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Hi Jack,

I own a 1990 Toyota Corolla GL 4 door sedan. I have a problem with my car as that it wobbles at low speeds(20km/h-40km/h). I have done a wheel alignment and balanced all my tyres but the problem has not been solved. All the tyres are inflated to 30PSI and there is no sign of a puncture in any tyres. I am from Christchurch so I am not sure whether the rough roads have made this problem worse.

Could you please guide me on how I could solve this problem.

Thanks heaps :)

It still sounds like a tyre related problem to me. You need to get the tyres checked for scalloping which basically means an unevenness (flat spots) in the tread inconsistently around the tyre. This can be caused by worn shock absorbers or incorrect suspension geometry.

You need to take the car to a wheel alignment specialist for a thorough check. And I suggest you go for a drive with the mechanic so they can experience the wobble with you.

I used to work in a tyre factory, and this sounds like a tyre with a uniformity problem called High Lateral forces. The tread and/or breakers are not in line with the tyre, pushing it left then right with each rotation. The only cure is replacement of the tyre. The symptoms are a gentle rocking from side to side at the speed you describe if the fault is a back tyre, and a steering shimmy at a higher speed if it is on the front.
A related fault is conicity, where the tread and/or breakers are in line with the tyre, but off to one side. This makes the tyre push steadily to one side showing up as a steering bias.