So, yes, I'm alive.....Admittedly, the vette has not gotten a ton of use the past few years. But at least this year that has changed. I've driven it much more often. I've got most of the interior reinstalled (no, most of the crap still doesn't work - wipers, I'm looking at you) but I don't care. Have to have at least ONE project for later, right? I did get some nice new Torque Thrust II wheels and new tires (17"). Such a huge difference! So, on to the reason for the post. This noise started happening before the new wheels and tires, btw. When the car is cold, I hear what sounds like a metallic sound - not a clicking, but not a banging either - from the left rear. I notice it in first and second gear, and maybe faintly in third - hard to tell with wind noise after that. After driving for several minutes, the noise disappears. It doesn't act like a bearing - the noise is not dependent on turning - it happens equally when going straight or turning with no change.Things I've looked at:

|UPDATED|9/5/2017 11:36:30 AM (AZT)|/UPDATED|

It it your heat riser?  Located on the exhaust manifold before the pipe.... Mine flips around and makes noise for about a city block as it warms up and opens.

|UPDATED|9/5/2017 2:25:32 PM (AZT)|/UPDATED|


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Nope. Coming from the left rear, and I have side pipes.

Good to see ya back on the Forums, John...been a while!
Does this noise sound like possibly a scraping noise? Grind? Rattle? Squeak? Does is sound like a sheet metal(tinny) noise, or something heavier?
It's possible it could be a wheel/hub bearing...they can make all sorts of different noises, depending on what is actually failing. Since you couldn't get it to make a noise with the rear suspension in the air, that sorta makes me think it is in the wheel/hub/rotor area. The reason being that there is no real pressure on the hub bearing(s), or brakes at that point. A u-joint noise would have at least changed with it in the air....raising the rear and running it in gear puts a tremendous strain/pressure on the outer u-joints.
It's very possible that a bearing is loose, and the rotor is rubbing somewhere on the caliper, even tho the noise seems to go away after a few miles. Might even be the rotor rubbing on the backing plate.
If you can, get the rear back up in the air, and check for ANY play in the hub bearings on the left side by grabbing the wheel/tire at the 12 & 6 o'clock positions, and push(top)/pull(bottom) in/out, and see if there is any noticeable play. You might need someone to look under the car directly at the u-joint flange on the hub(where the axle bolts up) to see if that flange is moving. Mind you, there will prolly be some play in the axle yoke where it goes into the diff, but we're not looking for that at this point. We want to see if the flange is moving independently from the spindle support. Ideally, you want to see/feel absolutely NO play there. A bad/loose bearing will show up by watching the flange move as you wiggle the tire/wheel assy.
hth

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Joel Adams
C3VR Lifetime Member #56    
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

If you have a baffled insert in the side pipes, it could be a loose baffle.

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1973 L-82 4 spd

Thanks for the responses guys