Contour Enthusiasts Group Archives Forums General Troubleshooting tire thumping

if my tire/s appear to thump on each revolution,could they be out of round?When moving at idle I can actually feel a 'bump' at each revolution.Tire rotation did not seem to help.The right front appears to have more noise than the other three.Could be that is where I focus my ears.
If not the tires what in the drive train might cause the thumping/bumping feeling?
(Michelin x-ones on all four wheels)

Sounds like a tread separation. Did you visually inspect the tires for any bulges or other irregular wear?

I'll give it a shot...

Without hearing/feeling what you're talking about, I'd consider one or more tires of inconsistent quality (although Michelin is often highly regarded for quality), or a bad bearing to be the most likely culprit.

If you're "feeling a bump" while rolling along at idle, you ought to be hopping all over the road at highway speed, or at least at certain speeds where the suspension resonates. Even if the wheel is perfectly balanced, an out-of-round tire or wheel is causing the suspension to move, which transmits vibration to the chassis.

Get your wheels spin-balanced, and watch them from the side as they spin in the machine. Any significant out-of-roundness would be visible. (Of course, the center hole in the wheel could be off-center while the lug holes are properly located... )

if your tire isnt visibly bubbled then you may have a bent axle

I'd suspect the Drive Axles/CV joints or bearing if you hear the noise at very low speed.

I rencently developed the same problem after changing to SE rims. Shouldn't be the bearing on because it didn't do it before. I suspect the tire, and am waiting for them to wear out.

Did you lock them up recently? If so, you flat-spotted them. Nothing you can see but you sure can feel it. If you notice it more when the car is first driven then it's because the tires are cold and the flat-spot they got from being parked is taking a while to work itself out. If they're actually going thwack-thwack-thwack-thwack then it's a ply separation in the tire and you want to get it taken care of ASAP. Try jacking each corner up so the tire is just off the grouns and spinning the tire, while watching the gap between the tire and the ground. Any out-of-round issues will become immediately evident.

Recently our Caravan suddenly developed a vibration that was felt at all speeds. When I jacked up the RF wheel, I found a very noticeable bulge in the tread. New tire time. There was no internal tire damage, but there was a bulge in the tread, nevertheless.

i've got a thump...need new tires. Rear passenger is starting to show signs of seperation. Check it out man!!

If it is only a slight thump and it is only there when the tire is cold, it could be that the tire has taken a set from sitting overnight. If that is what it is, it goes away after driving a mile or two. Tires with nylon cords in the sidewalls are the most prone to this. The Goodyear Eagles used on early Mark VIII did this and Ford's recommended cure was to install Michelin tires.

I am more prone to think that you do actually have a tire problem though. The advice to check the tire condition, especially for bulges and seperation, is excellent advice. Michelin has not been ammune to such problems.