I am having an issue with my '99 isuzu rodeo. It is bumping into gear when upshifting and downshifting. While in park if I shift into reverse it makes a pinging sound....Also it will not go into 4WD. ????DOES THIS SOUND LIKE THE TRANSFER CASE???? Has anyone here had to replace their transfer case before??? What was the cost?? BTW: I have already checked the tranny fluid and it was actually a little overfilled so I drained a little fluid out to normal levels. I hope I don't have to replace the tranny....I can imagine what that would cost....considering I only paid $2000 for the truck I may need to weigh my options if that's the case.