Thumping Feel

[WWII HiStOrIaN]

So I was in my 97 GT the other night and it's the 248a package so it has no ABS. I was in a situation where I had to slam on my brakes at 45mph and all four wheels locked for a solid distance. The roads were dry and there was tire smoke but now I can feel a thumping while driving which feels like it's coming from the right rear wheel. I have tires with decent tread on them. I inspected the wheels nothing seems damaged and all my lugs are tight. Did I break something or did I flat spot my tire? It doesn't seem flat spotted from visual inspection but I'm not sure. The thumping is pretty noticable and happens at all speeds.

Thanks,

Keith

 

[Neuron]

Take it off and inspect and if nothing apparent then move to front and try it. Sounds like tire but.......

 

[Old88Vert]

Hi Keith,

Did you ever figure out what your issue was? I had a slight thumping in my car while rolling slow on the Freeway til I locked them up on the freeway. The next time I drove it I thought there was a piece of wood or something on my tire. It comes and goes but is there everyday. Replaced my diff carrier and all the bearings and rear U-joint with no change. Im thinking it's the AOD now?

 

[Mattstang04]

You probably put flat spots in the tires. Its not necessarily something you can see but I've done it too. When the car skid it actually flattened out the parts of the tire that were making contact with the street.

This is really likely to be your problem.

 

[Old88Vert]

Thanks but the thumping comes and goes as well as intensity. I'd think a flat spot would be very consistent in its appearance.

 

[squeak93]

Check the trunk for midgets with baseball bats. Report back results.

 

[Neuron]

Take off wheel and replace with spare or another wheel tire(screw the donut tire I carry a full size spare), drive car. Repeat until noise disappears or done with all four wheels.

 

[Mattstang04]

My first post was for the OP. Old88, your situation sounds similar. Tires out of round are worth checking and cheap assurance of a problem before an expensive transmission rebuild or replacement. My 2 cents. Let us know how it goes.

 

[Old88Vert]

Thanks for advise, I'll have to check but as stated the thumping comes and goes in intensity it's most appearent ~30 mph. It was there before I put new tires on but very slight which changed after the lock up on the freeway. Also the heavy thumping came after I parked it for the weekend and did not thump immediately after the lock up on Friday.