I have the exact same two problems with my 2002 Jeep Liberty Limited (4WD) which I purchased second hand several years ago. A dealer replaced the speedo sending unit and the speedometer worked for about a month and then quit. I have since replaced the sending unit again, but without any success. The vehicle also sometimes stalls when slowing down. I suspect that the torque converter may not be unlocking, but that is just a guess. I haven't checked the wiring yet for an open or grounded circuit because of the difficulties in isolating the correct wires in wiring harness. Also, the fuse is not burned out. I plan on checking for voltage at the sending unit. If there is no voltage when the engine is running, then the problem may be in the wiring or possibly the speedometer.
I have a perfect 2002 Jeep Liberty but with two problems, the speedometer does not work and it stalls when you go to slow down.
The speedometer has been a problem for a long time and I have tried everything and even the dealer cant fix it, except temporarily. They changed the sensors on the outside of the tranny but within a few days, the sme problem.
I had everything looked at, you name it i tired it.
Any ideas on this would be great.