Does car instability driving on diamond ground pavement indicate something?

Question

I've been noticing recently that my car seems to wobble side to side a lot more driving on highways that have those diamond ground sections which are like long grooves in the direction of travel.

I'm wondering if this says something about my suspension, alignment, tires or really anything along those lines that I should get looked at.

Driving on those sections seems to feel like driving on a windy day almost but with more side to side oscillations than one buffeting blowing direction I have to correct for. I'll watch out a few more times to confirm but so far this section of freeway has seemed more unstable the few times I've ridden it in the past few months.

Answer 1

I dont think you have very much to worry about. I suspect the "unstable* feeling is a result of the interaction of the tire treads/sipes with the linear channels from the grinding.

If the car makes you queasy, try a motorcycle. The same effect on a steel mesh bridge deck, after a rain storm, made me pull over and check if my heart was still beating.

Speeding up makes it worse, as the interference between tread and groove occurs more frequently. On the other hand, slowing down makes it worse, as the weight transfer seems to add more load on the front tires where the effect originates.

However, the "unstable" feeling is just that, a feeling, and the momentum and intertia of the vehicle is fine and actually quite stable.

I think it's just the tactile clues you feel through the steering wheel feedback exactly mimic the sensation just before a major loss of traction.

Creepy!

Answer 2

The grooves cut into the pavement are approximately in the direction of travel. However, they are not exactly in the direction of travel. The force you feel is the result of the truck wandering across the roadway as the grooves were cut.