I was driving and noticed my speed gauge was jumping down then back up.got a quote from a auto shop to fix both speed sensors for 269 is this a decent price? also wondering if this is why my car won't shift into gears as I read about the transmission going into limp mode to protect itself from damage due to it not reading the mph correctly therefore not knowing when to shift at the right time so it locks into gear and won't shift no matter if your going 40 or 70 mph.sometimes the speed sensor works fine and i have no problems at all but other times the speed sensor won't work and the car will drive but stay stuck in 1st gear but will increase speed but not shift the gears

 

i have a similar issue on my 2000 stratus se 129k mi
i replaced the input and output speed sensor and now i am reading a trouble code of engine speed sensor malfunction P0725
i am awaiting clarification or other ideas from other experts, but after research i have found that a lot of people had this issue and was pointed toward engine speed sensor/crank sensor
if you find anything let me know
and btw both sensors on the transmnission cost me 15 dollars each and took me 3 minutes to replace with caveman era tools.... dont pay that much for them

 

thats good to know i figured it wasn't that hard to do.I'll keep you posted on this as I'm going to take it to auto zone and have them do a error code check to see if it gives me any codes i can use to better pin point it.I also noticed it only does this at random as sometimes its fine and other times its not.I've noticed it also does it moreso when its very very cold out.I've noticed if i turn off the car and then start it back up the issue goes away.