Drive line noise mystery? Solved

[Chamberpains]

THE FOLLOWING IDEA IS VERY DANGEROUS AND CAN CAUSE HORRIBLE DAMAGE IF DONE IMPROPER!!

Here's an idea to expose any problems in the Driveline. Chain your drive axles tight to the frame rail with the air suspension fully engaged. You want it fully engaged to keep proper Driveline angles. If the air is out or they are just hanging you will get driveline angles that will cause grinding noises in the Driveline.Then pick the whole back end up to get the wheels off the ground. Put it on jack stands and frame stands the more support the better and safer. And make damn sure it can't fall off of them. Then you can essentially Drive the truck through the gears without moving. This is real good at exposing noisy rear ends, out of balance or bent drive lines, noisey transmissions and clutches, out of round or poorly mounted drive wheels. You can hear and visually check all components at speed. I never had to take one above 30 mph to expose noisey parts and far less mph to see unbalanced or bent parts. You will not need to use the accelerator pedel. You can just put it in the gear with the speed you want to turn the drive line at. The engine at an idle has more than enough torque to turn any gear from a dead stop. You do not want to do anything fast such as accelerating or braking because it will snap driveline components or break gears. Remember there is no weight on the wheels to absorb the output of the engine or for the brakes to not over react. You want to be very easy on taking off and slowing down. Also make sure the wheels are completely stopped before trying a different gear or speed.

USE AT YOUR OWN RISK. THIS METHOD IS VERY DANGEROUS!!

I've had great success using this method to find those hard to find noises or shimy and shakes at certain speeds drivers complain of.