My Father has a 2002 Mazda Tribute, 3.0 v6. 4-wheel drive. Recently he became stuck in deep snow in his alley way. He trieded placing the vehicle in 4-wheel and 4-wheel low. He tried forward and reverse to break the vehicle loose. The next day he found that the reverse on the vehicle was not working. High engine rev but went very slow in reverse. We also found that the 4-wheel drive was not engaging. The front wheels would spin but not the rear. Driving the car forward works fine. When in 4-wheel the dash light signals 4-wheel drive, but does not appear to be engaged. Any ideas on what may be the issue with his vehicle?