I have an '07 Limited with a Hemi and I've rarely ever shifted it into 4WD low. A friend of mine told me to shift into 4 low every now and then to lube the gears. So I went off on a dirt path and shifted into 4 low, drove for about 100 ft then shifted out and drove off. Now my commander makes a strange clunk directly under the driver seat when I start, stop and turn to the right. I went off road again shifted into 4 low for a bit then back out into 4 high and now the clunk is gone. Is this something I should be worried about? Did the gears just not line up correctly when I shifted it out the first time?