The noise no man can hear

chevrolet
trailblazer

#1

My trailblazer is making a noise that is triggered by a turn in either direction. It is a metal clanging noice that speeds up and slows down with the wheels. It is not an engine noise. I have had three mechanics look at my vehicle and drive it - none can find anything wrong or hear the noise. Any ideas on what it could be?


#2

Many women have more sensitive ears than most men and hear higher frequencies. Furthermore, mechanics may have less acute hearing from working around noise all day long. Since the noise speeds up and slows down with the wheels, you may have a wheel bearing that may be causing your problem.


#3

Thank you for your answer - good point about the mechanics working in alot of noise all day - I hadn’t thought of that. I should of mentioned that I have been told there is nothing wrong with the wheel bearings, universal joint, ball joints, shocks/struts or brakes. The noise comes and goes and the performance isn’t affected. I am just worried that something will break at the most inopportune time(as it always is). Would a bad drive shaft make a noise like that(the oil change guy said he thought that could be it). Thanks again!


#4

I don’t think it would be the driveshaft, but it might be the constant velocity universal joints at the ends of the drivshaft. Keep monitoring the noise.
My mother and my dad were both excellent musicians and had very good ears. Yet my mother could hear noises in the car that my dad never heard. My mother was always right–there was a noise.
Men also aren’t as sensitive to noises as women. When I was growing up, we had a car that had a really noisy differential. It didn’t bother my dad a bit. However, the whine drove the rest of us nuts. My dad finally decided it was better to have the rear axle fixed than to listen to the rest of us complain.


#5

Thanks, will do. I am a little paranoid about breaking down because the engine seized in this vehicle during rush hour traffic on I-75. It was a traumatic experience for me(so was replacing the engine). Since then, I have tried to be very proactive about maintenance and any noises I hear. Thanks again. :slight_smile:


#6

If tis a clicking noise when you turn, Then its your CV joints. You are going to want to replace these soon, because when they go out, the car will not move at all, no matter how much you rev your engine. They are part of your driveaxle, so your going to have to replace the whole driveaxle. There is a driveaxle on either side of your vehicle, connected from your transmission to your front wheels. Try to find out which side the noise is coming from, and replace the part on that side. Or if you want, replace them both.


#7

My hearing is damaged too the point I need hearing aids, all from shop air tools. Another thing most mechanics miss is outside air leaking into the car at dash level as most have their legs covered.


#8

It’s not a clicking noise, it sounds like a piece of metal is hitting another piece of metal(clang, clang, clang) in time with the wheel rotation. However, I will write your suggestion down, too. Thank you.


#9

All Trailblazers that I know of are RWD. Some have 4WD option. It would be best if you stated the year and whether or not yours has 4X4 option.

I replaced a front hub bearing assy on mine last year. Bearings tend to groan or whine based on wheel speed not click or clank. I recently experienced something similar to your description. Turned out to be rust ring on outer diameter of the rotor contacting the backing plate. The backing plates are wicked close to the rotors in a couple spots…


#10

Mine is a 2002 with 4WD. So, if I take it back to the mechanic would they be able to see if the CV joints are bad or if there is something wrong with the rotor/backing plate? And, if it is a CV joint, how expensive is that to replace? Thanks for your input - it is so helpful!


#11

Twin, your idea sounds promising. If Laura were to jack up the front wheel and spin it, would she be able to hear the noise if she has a similar issue?

It’s probably worth a try.


#12

See if the repair shop has a young mechanic. Kids have better hearing. He doesn’t have to know how to repair it, but he can help find the issue.


#13

This tire/wheel assembly would make maybe one revolution with a good hand spinning, not enough to make a call.


#14

Before getting too deep, have you removed the wheel covers and checked that the lug nuts are all tight? Wheel covers can make noises. Drive without them and see. Or hear. Or not.


#15

I mention the backing plate as a “what if they can’t find a cause” kind of situation worth investigating since several people have had trouble finding it. It happened to me. I had the benefit of hearing the noise in person and then knew what/where to look for it. After ruling out another bearing failure or an axle issue, I started looking for obscure reasons. The rubbing on the backing plate is hard to duplicate by hand with the wheel jacked up for two reasons; one, with the drag associated with 4WD components, you’d have to be the Hulk or Ahhnold (sic) to rotate the wheel fast enough and two, it takes a lot of lateral force to deflect the rotor even 1/32" to make contact with the backing plate. Something a large truck going around a corner does with relative ease :wink: The rust ring was easily removed by light hammer taps along the outer chamfered edge of the rotor and the relief was immediate- no more noise.

Now that we know you have 4WD, that brings a few more components into the mix. A good tech should be able to easily diagnose your problem- especially if it is a “clanging” noise. That’s what’s tough about diagnosing with words, what is clanging to one might be intermittant rubbing to another for example. Have to hear it in person…


#16

I have had the tires rotated, new shocks & struts, transfer case & differential serviced since this noise has been around & I mentioned the noise each time, wouldn’t the repair person look at cv joints/axles, etc? Also, when I had the tires rotated, they looked at the brakes and said that one of the rotors had “scoring” on it but nothing needed to be done. I probably should have mentioned that but I forgot about it until looking over my records/receipts. Would that make a period noise that sounded like clanging of metal(or rubbing of metal)?


#17

wouldn’t the repair person look at cv joints/axles, etc?

You’d like to think so but apparently, they may not be as diligent as one might expect. You don’t say where you’ve been having this work done. Not all establishments have the same level of service or expertise…

Here’s what I would do- don’t wait to mention it along with some other work. Take it in to a reputable dealer, or independent familiar with your vehicle make/model, specifically for this issue. This will insure they concentrate on this specific problem. Ask them if it would be OK to go along with the mechanic on a test drive to verify it makes the noise and point it out to them. “See, that’s the noise I’m concerned about right there, under these conditions”. If they can’t figure it out then, prayer might be an option…