Ok, I just got a 97' and when i turn it on and put it into reverse or drive sometimes it pops when I the gas. When i say pops I mean the it shakes the whole car. Also when i back up out of a parking spot and put it into drive, I hit the gas and all it does is rev it up like its in park or neutral and it did that twice today. Can you tell me if this is normal and a known problem or should i take it to a mechanic ASAP. Please help me with this cause I dont want to replace a 4WD transmission.