Problems with my '97 Mustang

Hello, I have a '97 v6 mustang. It was my grandfather’s car and I bought it about a year ago. It was pretty well taken care of, but it is older. About 3 nights ago, me and my dad changed out the plug, plug wires, and brakes pads. Ever since then the car has been driving not so smooth. It idles fine and drive smooth…sometimes. A lot of times it feels like I’m driving on a horribly paved road, even when I’m not. I’m not sure why this is, and it started literally after we changed out the things I mentioned above. I’m not sure why, since those are pretty standard tune up items. I had a Buddy of mine ride in it with me and he says it might be a wheel bearing/ hub assembly. But I’m not sure. Like I said its just not a smooth ride anymore and really the only way I could describe it is driving down a horribly paved road. Just bumpy and a lot of vibrations. Any ideas on why or what I could do?

When you replaced the brake pads, this meant the vehicle had to be raised.

Sometimes when you raise a vehicle for whatever reason, the suspension hangs beyond it’s normal ride height.

Doing this can sometimes mess up the valving within the shock absorbers and this results in a ride like a buckboard.

Try pushing up an down on the fenders to see if it’s hard to get the suspension to compress.


I talked to my dad about it (I’m no mechanic by any means) and he said that it may be that, but he doesn’t know why it would be because we didn’t use a lift, we just used a heavy duty jack and lifted the entire rear end/front end up all together.

Unless you jacked up the front suspension under the lower control arms, the front suspension was allowed to hang.


Is the ride quality much poorer than before? Or is there just some weird sounds coming from the wheels? A growling sound coming from the wheels (like it would sound if you were driving on a roughened road surface prior to the re-paving crew coming in) , that could be caused by a problematic brake pad job, or it could be caused by problematic wheel bearings. the latter could just be a coincidence, no relation to the work you did. Or it is possible to damage wheel bearings when doing brake work, especially if it is done incorrectly. Generally wheel bearing damage wouldn’t occur just replacing pads, but if the rotor (or drum) had to be removed and was rust-stuck on, freeing it up might damage the wheel bearings.

The idea above of suspension damage caused by jacking the car is possible; but unless your Mustang has aftermarket suspension parts, seems unlikely.

It’s a huge noticeable difference in the ride quality. I think there might be a sound, but I’m not sure if it was there beforehand or not. I am deaf in one ear so its hard for me to hear things a lot of times. If I had to make an assumption off of what I know, I’d say it would be a wheel bearing going bad. But again I’m no mechanic so I cant say for sure.

A bad wheel bearing wouldn’ usually produce what you describe as a “huge noticeable difference in the ride quality”. So I doubt it is the wheel bearings. That pretty much leaves these two as possibilities

  • Shock absorber is out of whack as a result of jacking
  • Some other part of the suspension system got damaged somehow.

I’d start w/the idea above, press down on each of the four corners of the car and see if it behaves as you expect it to. If you don’t know what to expect, try that experiment on a similar car so you can calibrate yourself what the push test feels like and how much the corner of the car bounces before it settles down when you let go. On my older Corolla it doesn’t take a huge amount of effort to push the corner of the bumper down, and it settles back to where it was upon release after about 1 1/2 bounces. On my friend’s newer Corolla it takes somewhat more effort to push the corner down, and it settles back to where it was after just 1 bounce.

Have you verified the lug nuts were properly tightened/torqued?
Almost sounds like loose lug nuts to me.

motor issue? misfire? you changed plugs and wires. due to age. was it running ok before you did this? you drive at 30mph. it feels rough. like suspension issues. you let off gas and coast. still feels rough? i assume you will say it feels ok on a smooth road but may or may not feel rough on a poor road. sort of comes and goes. you could have a shop look at it.