OK I have a 93 Jeep Wrangler and I am having the same problems. No problems in 2WD and 4WD drive works in forward motion however when making hard left turns. I get a loud banging noise as well. This is not a Metal hose banging or a rubbing of the tires. This noise sounds if some type of gear is repeatedly slipping or someone is hitting my right side front axle with a 12 lbs sledge hammer. In another post I read someone stated the below. Can anyone add to the validity of his claim.
"That is a common issue for new Jeepers that is easily prevented from happening... never shift into 4x4 while on a paved surface. In other words, stay in 2wd when you're on the street.
The Wrangler's 4x4 system is a "part-time" system that was not designed for use on paved streets. It was designed only for use when on loose slippery surfaces. Dirt, mud, rocks, snow, or ice.
Why does it cause the steering to jerk back & forth & make it feel funny when you shift into 4x4 (4Hi or 4Lo) on the street? Because the Wrangler's 4x4 system mechanically locks the front and rear axles together so the tires on both axles must rotate at exactly the same speeds/RPMs. The problem is that when you turn left or right, the front tires must rotate faster than the rear tires and being in 4x4 prevents that from happening which is why the steering feels funny... the front tires are fighting with the rear tires.
Only Jeeps like the Liberty, Cherokee, and Grand Cherokee have optional "full time" 4x4 systems that can be used on the street.
The Wrangler's 4x4 system should not even be used on the streets when they are wet from rain. Even wet streets have too much traction for the Wrangler's part-time type of 4x4 system."