I hear a grinding noise at 20mph. noise goes out when moving faster or slower or when even touching the brakes. noise is there both when revving up or down, on 2WD or 4WD

mechanics cannot isolate it. any ideas?

 

Have you tried checking your bearings? Jack the car up so that your wheel is off the ground and give it a good spin. Better if you can get a mechanic's stethoscope on it while a buddy applies the spin.

 

If the bearing test's ok I'd pull the wheel and inspect the brakes.

 

Similar noise. Turned out to be the left front hub bearing. Take it for a drive. If the noise gets louder in a right turn, it's the left hub, or right hub in a left turn.

 

Thanks guys.
tried the stethoscope thing, couldn't hear anything particular. Pulled the wheel out, pulled the brake disk, inspected the pads for uneven ware, put it back together.
noise is a bit different but it is still there at 22mph exactly. can't hear it when driving faster than 27mph or slower than 20mph. doesn't change when turning left-right. doesn't change of you are on gear on neutral, 2wd or 4wd.

i'll take it to another mechanic this week

 

For what it is worth...….recently had similar issue. Welded a loose coil retainer clip as bolt hole was stripped. (perhaps coils was moving around and causing noise) Did the same with a stripped sway bar bushing (perhaps sway bar was moving around?) Also retightened steering box bolts as I had recently changed box out. One/combinations seems to have been effective. All were ideas I found online.

 

Only doing it at a certain speed sweet spot sounds like hub. Does it do it after it sits for a while and go away after driving it a bit?

 

as long as my speedo shows 22mph, the noise is there, like 2 metals grinding each other. touch the brakes and it goes away (becomes almost inaudible is the right description) if you manage to keep the speed at 22mph (I keep my foot on the throttle and push abit the brakes with my left).
tomorrow it goes to another mechanic. not specialized in JEEPs but lots of experience and patience. after all this searching I did, I would put my money on a joint or the pinion bearing and sealer (had the same symptoms with a Land Rover) although cannot explain why it goes away when I brake.

 

Thinking off the grid here but could it possibly be the speedometer cable ???

 

makes perfect sense!!! but can it be that loud? I'm running on mud/snow tyres on tarmac and can still hear it. I'll check though, thanks alot

 

could be a bunch of things, but if stops when you hit the brake Id start with the easy stuff, brakes dragging, Sometimes the dust plate rusts and hits the rotor too.

 

Thank yall for suggestions ideas and support. strangely enough it was the bearing. no play and didn't do thte typical worn bearing noise. it was too tight, almost not able to turn by hand...
fyi before getting there we checked and disassembled almost all the front axle

 

Make sure the axle nut is torqued to 175 ft/lbs / 237nm when the new hub is installed. Incorrect torque on this nut will cause premature failure of the hub bearing. Those bearings can be pretty expensive here in the U.S., I imagine in Greece they're going to be quite a bit higher.

 

Is it a heavy grinding sound? or is it lighter?
I had that on one of my front wheels a while back (lighter scraping sound)... turned out to be the thin metal guard on the back side of the rotor. Those things can bend pretty easily. Could vibrate starting at a certain speed like mine did. As when I did the wheel spin test and took the wheel off that backing plate did not look like it was touching when stopped.

**** will leave this in for future searches, but my bad... didn't read every post before posting my 2 cents to help.

 

No worries as far as I'm concerned, your input is always valued.