I had my car in 3 times at the dealership over the past week trying to diagnose a slight grinding/vibration(similar to a bad wheel bearing) noise coming up through the floorboard around the drivers side area. The first visit I was told to take off the 2.9 pulley, it's causing the belt tensioner to rattle(was not the solution). The second visit was a road test that ended up with the technician saying it was tranny related. The 3rd visit..tranny issue was ruled out and they said my catalytic converter was hitting my front sway bar causing this vibration. They wanted to charge me to make some adjustments to my exhaust since I installed my own GMPP catback. I told them the cat is on the downpipe, how in the hell could I have made this move by bolting on my catback. Is it even possible to adjust the pitch(position) of the cat/downpipe?

Updated today.....cat/exhaust was adjusted, no change. Dealership now believes my Sportlines are probably causing issues with the front axle, since it's a different angle. They want me to put the stock springs back on to see if that corrects the grinding/vibration. I know the sportlines tend to give most of us a small amount of vibrations, but there is something more going on around my front driver's side wheel.

I also got a new steering wheel center section (airbag/cover and emblem), somehow the Chevy emblem got dented...go figure! Replaced under warrenty...

 

depending on the hanger locations of the catback it could change the pitch of the down pipe. ive seen the stock cat rattle on the sway bar. but it still doesnt sound like your problem.

 

It's not a loud grind...you actually have to have the windows closed to really hear it. I thought wheel bearing or cv boot right away...

 

look behind the suspected wheel bearing, if it has what looks like glitter (your wheel bearing is shaving) then it's a bad bearing

 

if it was the cat on the down pipe it would be more of a rattling not a grinding. Is the sound constant? or does it only happen why you do certain things like turn or go over bumps?

 

I can only hear it if I keep it steady and slow in 1st and 2nd....by 3rd it's hard to hear. Almost sounds like it's going with the tire rotation. You would think the dealership could figure this **** out, but I think every road test they hear different noises than what I'm trying to explain.

 

you sure it's not something with your brakes?

 

bad rotor or sticky pad maybe?

 

warped rotor maybe. how many kilometers do you have? you damn canuk

 

16000kms...you crazy yankee!

 

update in first post....

 

darren, who installed your springs?

 

I did...with the help of a buddy

why?

 

did you make sure that the nut on the top of the strut was tightened all the way? if it was just a little loose it could cause hella vibrations.

 

yah it's tight, but I should double check it. It would not surprise me if the pitch of that axle going into the drivetrain may be the issue?

I've had the Sportlines on for about 8 months...maybe they are starting to cause undue stress on my front end components.

I'd really hate to go back to normal ride height, but I might try someday just to see if that is the problem. They will make all repairs required if I put my springs back on and still having issues.

I'm not getting bad vibrations, just hearing stuff....but I'm picky.

 

i dont think it's the springs, i'd be willing to put money on the strut nut. make sure the strut doesn't spin while tightening it. you may have to jack up the car a little bit.

 

I'm going to try....worth a shot.

How can I make the strut not spin this time....or will it be easier if it's actually mounted..it should not spin at all really...being on the car