1999 Dodge Durango • 131 miles

So I have a 99 Dodge Durango. It stopped shifting about 2 years ago. When I say STOPPED shifting I mean it shifts about 50% of the time. What is wrong? I have heard that maybe its a solenoid or maybe a tranny. How do I tell which it is?

May 19, 2012.

If the transmission fluid level and condition is okay-check/test the transmission range sensor if okay bring it in and have it pressure tested to find out more what'sgoing on-

May 19, 2012.