michaelhawk

Last month took the Hawk into my reliable shop for new front and rear brakes, and adjustment to tighten up slack in the parking brake handle.

I didn't notice at first, but the next day I hear a vibration under the car. It sounds like a heat shield lightly touching an exhaust pipe, and seems to be middle of the car or front end.

I can hear it at start-up and in slow motion about 50% of the time. I'm unsure about regularly driving for the exhaust would drown it out.

I crawled under there the other day and I don't see it being the exhaust heat shields. I don't know anything about brakes, before I call the shop back, I'd like a clue as to what it is.

Any ideas?

smitty2919

When specifically does it rattle? At idle? Low rpm at all times or only when hitting bumps?

michaelhawk

At startup / and Idle. If I'm moving forward or back slowly also.
Does it most of the time, not 100%.
Bumps don't make a difference.

zfastss

iTrader: (6)

Check the "over-the-axle pipe" of your exhaust where it literally goes over the axle near the gas tank where it splits back into 2 pipes. It can sometimes be really close to the suspension piece and vibrate against it when the motor twists (twisting the exhaust a little). The passenger side exhaust hanger bracket has some adjustability if you loosen the bolt on the hanger (you'll see a slotted hole where this nut is, where it can be slightly adjusted). At least on my slp loudmouth the adjustment is there. Not sure about other systems or the stock exhaust.
Hope fully that's it.

michaelhawk

^ Thanks, but its not at the back end, its middle to front of the car.

smitty2919

Get a video

michaelhawk

Good idea on the Video, it is 2016 after all - isnt it!

michaelhawk

anyone have thoughts on what that rattle might be?

Zmg00camaross

iTrader: (11)

There are a ton of little heats shields under the car. By the firewall and manifolds. If you could safely put it in Jack stands and run it and get under there and inspect.

michaelhawk

Found it!


The rear O2 sensor, drivers side. Snugged the damn thing tighter & all is quite again - well not all that quite, but no more rattling.

Dirtybirdy94

I just found a rattle I thought was a heat shield like you described. It turned out to be the shaft under the center console that prevents you from shifting out of park without pressing the brake.