I have a 04 Laredo that I just purchased a few weeks ago. It has 139K miles and it was running excellent for the first two weeks. Suddenly it won't shift out of 1st gear. rpm's just rev up and it won't go into 2nd. I have done research and have seen that I should have the governor pressure sensor and the governor pressure solenoid checked or replaced.?? Any ideas as to what else could cause this? reverse works fine. I know I have to take it in but want to have an idea as to what I am going to ask the mechanic what to check.

 

I have an 02 at about the same milage the same happened to me .just had both replaced , don't forget fluid and filter too