Hey, guys, getting a strange clanking sound from the rear end all of the sudden when coming off the line. Almost sounds like the muffler bouncing around or something, but its for sure is not. Sounds like its coming from the rear wheels area. Lifted the car up, and put it in first and released the clutch and the sound appears to be coming from the rear end or maybe the output end of the driveshaft area. Doesnt happen at all in reverse. Almost like something back there is bouncing around at low RPMs in low gears. Does NOT sound good.
Checked the rear diff bushing, and it still seems pretty solid with little to no movement. Isnt the mufflers. Again, almost seems to be coming from the diff area.
Any thoughts?
2004 6mt coupe

 

Check rear diff fluid level, axle shafts and propeller shaft u-joint for play.Aldo check ALL fasteners for torque, may have broken a bolt but it's still in place.

 

How does one just check the fluid level in the rear end?

 

Also, apparently if I put the rear end in the air (jack stands) the problem no longer exists.

 

Fluid levels are easy to check, there are two large bolt faces on the differential, one on the bottom and one near the top. Loosen the TOP ONE FIRST ALWAYS (in case it's seized, don't want to drain the diff and not be able to refill it) put your finger into the hole and you should feel the fluid level with the hole (you fill it by pumping in fluid until it spills out the hole).

If you're going through the effort to get to this point you might as well just do a fluid change, there's a magnet on the drain plug at the bottom, don't be shocked if you see a very small amount of metal shavings stuck to it (I mean VERY small) but if it has a large amount of metal heaped over the magnet you have a problem.

If you're still having a hard time finding the loose or worn component ask around at local oil change shops with a pit, see if they can have a technician stand under the vehicle while you reproduce the sound so they can physically LOOK at the bottom of the vehicle when it's happening. Usually if you throw them a $20 "diagnostic" fee they're happy to help if there aren't any customers to deal with.

 

Are you sure it's not the super common cv axle click noise?

 

I dunno, the axle click doesn't sound anything like:

It's more of a sharp "click" that's present in fwd and rev regardless of launch torque. OP should definitely search for a youtube video of the axle click just to rule out the sound though