So Friday night on my way home from class, my lsj started to make a wobbling/thumping sound ONLY at low rpm's and under load. When i let off the gas, the noise stops. Ultimately I need to lift the car up and get a look at it, but I want advice before I start ripping CV boots off and stuff. I'm thinking it could be throwout bearing, wheel bearing or half shaft?? Any other thoughts or places to check would be appreciated. Thanks

 

I hear the sway bar links and bushings go out and create a clunk. Search about that.

 

when wheel bearings start to go they make what most customers describe as a "growling noise". it's louder at higher speeds and consistant rather than a thumping type noise. throwout bearing should only make noise when the clutch is being applied, it doesn't turn the rest of the time. CV joint is possible although it should make noise under load at pretty much any RPM, again getting worse at higher speeds. if you want to check them don't start removing boots, just grab the shaft and move it up and down and side to side. you should be able to feel exessive clearence if they are making noise. some movement in and out between the wheel and transmission is normal, so don't worry if you feel clearence in that direction. swaybar links make a clunking noise when going over bumps, even small ones, but are quiet on smooth roads.

try getting up to a good speed and holding down the clutch. let the engine and transmission slow down. if the noise stops it is likely not related to anything that is still moving like the wheels and other rotational parts, or the suspension. if it continues then its probably not engine or transmission.

 

Yeah the noise has become louder and more consistent. I can't lift my car up here or I would, I'm thinking it has to be one of the half shafts or the intermediate. I'll put it on the lift at school tomorrow hopefully get a good look. Thanks for the tips

 

Odd diagnosis, but did you install an intake recently?

I installed a ZZP one and I didn't put in the bottom bolt because I didn't feel like drilling a hole, and with my axle bind it taps the fender liner, which creates a louder thumping noise than you would think.

I also have a clunking noise (feels like the entire front suspension is loose) when I hit even the smallest bump, which is most like end links.

 

Wow I just realized something, I will check it out tomorrow. I had an issue with my K&N intake where the stock plastic pipe kept sliding off of the metal pipe and had to loosen the bottom pipe bolt.. come to think of it I don't remember tightening it back up. It's crazy that it can make such a god awful noise! I'll check tomorrow AM thanks toastie

 

And yeah I get that "clunk" when I hit every little bump on the road too. My front struts only have about 10k miles on them, I really just need to set aside some money and replace a bunch of wear items. I'm at about 78k miles so it's about time for new bushings anyway. I just hate fixing things before they're actually broken, feels like a waste of money although it really isn't. PMI.

 

to check your control arm trailing bushings lift the car up so there is no load on the front wheel then stick a prybar or big screwdriver between the cradle and control arm at the bushing and pry the control arm up and down. do it from the top add from the bottom of the arm so that you are streching the bushing up and down. watch the rubber of the bushing and look for any seperation from either the metal ring around the outside of it or the round bolt sleeve on the inside. if the bond is seperating, replace. if not, you are good to go.

 

My throwout bearing is going out. I can hear my clutch disc slipping in neutral so I'm doing the clutch this weekend

 

im gunna go with
A: its a cobalt. front end is always making some kind of noise

 

Got that right.

 

"noise" is a polite word for it. Haven't been driving it for the risk of blowing something up. It sounds like death

 

then replace your wheel bearings. their easy to do, and pretty cheap.
do the axels while your in there. would probably be a good idea.

you know it will ride like a dream again when their done :P

 

I was thinking wheel bearings could be part of the problem, but in my experience they usually *usually* make noise in correlation to wheel speed. I'm getting a new set of them too because they'll need replaced at some point. I'm going to be changing out the clutch tomorrow.