Bang in left rear please see posts in suspensios on TLC Help. Thanks, Randy

[Hank70SS]

Good luck Randy. Those type of problems are really hard to help with over the internet. I'm sure you'll nail it.

[zombie1969]

Originally Posted by Hank70SS

Good luck Randy. Those type of problems are really hard to help with over the internet. I'm sure you'll nail it.

Hank hit the nail on the head.I worked for GM as a tec for several years and will give you this advise.You said the u joints are tight and greased.That doesant mean they are good.You said its under torque when it happens so the first thing Id do is remove the drive shaft and remove the joint caps.Ive been bitten in the rear a few times being lazy.Remove the rear wheels and drums.Check the stud hols in wheels for damage or a cracked wheel.Also Ive seen this before.A crack in the flex plate if you have a auto.This most likly will not resonate to the rear but its good to check everything.You may hear the noise comming from where you think it is and its resonating through from where you would never think of looking.I had one before that made a banging noise under power and turned out to be loose/worn carrier bearings.This is something you wont find just by looking under the car or spinning the wheels on the lift.Another thing to check before tearing into it is the exaust.If its comming in contact anyplace you should see something.A broken dr side motor mount will cause exaust noise also.Bottom line is get a 12 pack and a good light to inspect everything.Good luck and keep us posted on what you find.