Scootin159

My car's making a funky noise, and I'm having trouble tracking it down. Do any of you have any ideas on where to look next?

The noise: It's a wheel-speed related tick, tick, tick as I'm coasting or accelerating lightly. At low speeds it actually get's louder (it's loudest when I'm just crawling - arguably more a 'clunking' then), and nearly disappears at highway speeds. I don't hear it through the car, but only echoing off other objects with my window down. It disappears IMMEDIATELY with even the slightest of brake pressure, and either disappears or is inaudible with anything more than 1/4 throttle. Cornering has no impact on the noise (no softer and no louder no matter how hard I push it).

My initial diagnosis was CV joints - but I've since replaced all of them. It fixed a different noise (my car makes a lot of noises), but not this one.

My second diagnosis was wheel bearings - I've since replaced any that were even slightly questionable (front left and rear right), and once again - fixed a different noise, but not this one.

Any other thoughts on what it is, or how serious this could be? I don't care about the noise itself, but more so the possible issue it's representing.

My next thoughts are on the transmission output shafts, I do know that I can move the inboard CV joint laterally 1/16th of an inch relative to the transmission case on the passenger side. Is this an issue, or 'normal'? Could it be the source of the noise? Am I likely to blow up the transmission if I run it like this (I have 5 autocrosses and 2 DE days in the next 4 weeks)?

I've already taken it to a few very qualified mechanics, and they've even gone to the extent of running the car while it's on the lift and listening with a stethoscope, but haven't nailed it down (it doesn't happen on a lift). Their recommendation is to just run it until it gets worse and then it will be obvious, but my concern is that 'obvious' will be when a wheel falls off at the track.

long post cliff notes: I've got a weird noise while coasting, it's not wheel bearings or cv joints, what could it be?

krystar

what about brake pad retainer? could something be loose or catching on the rotor? i'm going to guess that if you jack up the wheel and spin it by hand, it doesn't make the noise heh.

Scootin159

No such luck - I've tried that may times. I do hear the standard noise of pads dragging on the rotor, but no tick/click/clunk etc.

krystar

can u tell which side it's coming from at least?

Scootin159

I THINK it's driver's side, but that's only because I hear it coming through the driver's side window. It could also be that I'm just sitting closer to that side.

krystar

i think a run-alongside diagnosis in a parking lot is in order

i had a ticking/dragging on mine too. turned out the phillips screw that held the rotor/hub wasn't all the way tight. while i was there, i tightend the castle nut a bit more for the bearing too.

xsboost90

got a nail in your tire?

whalebird

If you replaced the cv/drive axles, go back and retorque the axle bolts. This is a very common problem. The seals will colapse a little leaving the bolts loose. The bolts, if new, will also stretch. If it seems to be coming from the drivers side, I would question the left rear wheel bearing. Try to torque the big axle nut on the rear hub. This will take a real big torque wrench (like around 425ft/lbs). I will get the exact torque figure if you need it. An impact gun will not do the job-you must use a big socket and breaker bar.

peanut

good way to amplify the sound is to coast down a slight slope next to a wall .
if you turn the engine off even better but remember you'll have no brakes or steering
I tried that last year by opening the drivers door and hanging out of the car whilst it was rolling.
Not recommended kids ... I nearly lost my head and the car door but I did identify the noise.