no 3rd gear

i have a 96 concorde 1st and 2nd gear shifts fine 3rd gear is like neutral then goes in limp mode, was driving normal when this happened slowed down to turn, no noises, fluid is full and clean, has 131,000 miles.

Take it to a dealer and get it scanned, a code in the TCM could read as a solenoid pack problem, sensor problem, or something worse requiring to having to get it rebuilt or replaced.