just got back from the DMV $275.00 later the Durango is in my name,it's a 30 mile trip to the DMV on the way back home i noticed when it goes into 4th it's not as smooth as the other gears,the check engine light is on,went to the auto parts store,had them scan it.they said the code was was for a sensor for the trans,the people i bought the rango from only used it once a month,they started it to keep the battery charged and to move it out of the garage,getting ready to do a trans filter and fluid on it.what else can i do at that time,and where is the sensor that might need to be replaced, it a 2000 with a 5.9 the trans is a 46RE,it's only forth gear that it seems to have a little shift problem,

 

Get a hold of an owners manual and check the maintenance schedule. Catch up on anything if there is not documentation that it’s been done.

 

got it covered,did both differential's and the transfer case, picked up the trans filter and fluid,put a new alternator and new battery, and going to do a oil change next,

 

When I get an older vehicle, I do the fluid changes as soon as possible. Oil and filter, drain and refill differentials and if the transmission has issues, get it too. I also change the coolant and thermostat. That way I know when it was last done. I also will unhook the battery and remove it from the vehicle. I then rinse the battery tray out and once it's clean, put a little sodium bicarbonate on the tray where the battery sits. Even if it's plastic, the hardware can corrode and ause problems down the road a few years. When you put the battery back (remember to unhook the negative first and reattach it last) clean the battery connections and put a little dielectric grease on them. This lubricates the connections and seals the hydrochloric acid away from the metal parts. If any of the small ground look iffy, replace them and clean any that look nasty.

When ever you do some brake work, give the system a good flush while you're at it. People marvel that my old stuff lasts so long.

 

You need the code # to know what "sensor" is the issue.

 

got the code and a new sensor,