350slide

Just bought a 2003. There is a low pitched thumping noise coming from one of the front wheels (i think). It is very noticeable at low speeds (less than 30mph) although you can hear it very faintly at speeds up to about 50mph. Above that and you can't hear it at all. The frequency of the sound definitely matches the frequency of the wheel revolutions.

Any ideas what this could be? Wheel bearing? Tire flat spot? Any common problems with Z's that result in these symptoms? What are the best ways to diagnose the source of the sound? Thanks in advance.

SQuaLZ

Is it when you hit bumps? If not when does it happen?

SQuaLZ

wheel bearings, in my experience, normally hum instead of making a thumping sound so I doubt that.

I had a thumping sound on my B13 that happened every time I hit a bump on rebound. Turns out it was the strut mount.

350slide

It happens under any condition. Bumps in the road do not change the sound. Happens under acceleration, deceleration, cruising. Happens regardless of which gear I'm in and whether or not the clutch is engaged.

dcains

iTrader: (15)

I'd check for a tire defect.

SQuaLZ

This!

The hardest part is that you just got the car, so it's not like you can figure out when the noise started and what things were done and changed on the car that maybe affected it.

But I would try to pinpoint which wheel is making the noise and either take the wheel off and check the tire or just look from the wheel well.

350slide

Okay thanks. I'll take the tires off and check them tonight.

fbi350z

5 year old thread!

But my 06 has the exact same noise as described by OP...

hey OP, if youre still around, did you ever determine the cause of the thumping?

I thought it was a wheel, so I replaced a rim and put on two new front tires. ....nope...sound is STILL there. Anybody that can please share any ideas , greatly appreciated. thank you

Rasean Lawson

This is also happening to me now. Thought it was the front wheels themselves, replaced both and still having the same issue. I’m thinking it may be my lower ball joint since there is a bit of play there.

OldManZFL

If it's not the bushings in the lower control arm then it's the wheel bearings themselves. You can get them relatively cheap with the hub pre-mounted. Whop Whop Whop and/or Thump Thump Thump sound, louder at speeds under 40mph. Both these parts are common for replacement. Whiteline for the bushings kit and any mid priced wheel bearings should do the trick, i ran some no names on my Z for 4 years without issue. Please note, if the problem is either of the suggested fixes, do both sides of the car (all of front or all of back) at the same time, don't try to do just 1 corner or you will find yourself back in the same spot you are now in short order.

Spike100

You have a 16 year-old-car. The noise you hear is probably coming from the upper and/or lower control arms. The bushings are shot, and it's also likely you need to replace the control arms as well. I have a 2003, and I replaced both control arms, and also upgraded the bushings. The car drives like new now.