drive shaft / pinion angle problem?

while driving my truck, if i let the rear down real low, below a certain psi, i hear a squeaking sound under the bed. I have a forward triangulated four link with the bags on the upper bars, and i don't know if the pinion angle is off or if the drive shaft is being pulled slightly out of the transmission or what? i have no problems with anything at ride height or higher. any suggestions?

my driveshaft scrubs the fuk out of my cab floor when i ride low...i'm going to put a tunnel in soon...

is your bag rubbing on anything? when deflated the bag is bigger in diameter...it may sound dumb but rubber squeeks when it rubs on metal...

doesn't seem like that was 7 months ago, time flies. i did find the problem though. nothing was rubbing, but the driveshaft was being pushed into the transmission and was making that noise, so i adjusted the four link bars out some to pull the driveshaft back. i haven't had any problems since. thanks anyway though.