If the pop turns into a squeek like an old door you should look at the rubber grommet at the rear of the torsion bars. I have one of those gone bad and everytime I turn lock to lock I get a squeek. This happens when the tires pull the frame and suspension a little to the front or back depending on wich way I turn thus draging the torsionbars in the rear mounts. A bit hard to explain in writing but when you take a look at how they are set up you'll understand. A decent amount of WD-40 or anything equalivent will do the trick.

1987 SWB Pajero 2.5 TDI on 31" rubber waiting for a hip replacement and bigger shoes