Well, I got the new trans in and upon 1st test drive my speedometer was way off so I decided that the other truck probably had a 3.55 rear where mine is a 3.92. no big problem, I just swapped in my speed sensor from the old trans and it seemed to work fine for a day or two. A couple days after doing the swap I headed out for about a 500 mile trip and after about 30 miles I noticed that I just didn't seem to have the cruising power that I used to. After about 350 miles I see my shift light come on and my speedo start to drop. I went on for a little ways shifting gears, shutting it down and re-starting, on and off the throttle and finally the speedo just quit altogether and it tried to die every time I'd push in the clutch. I limped into a truck stop and looked around the speed sensor but I didn't see any leaks or anything obvious. I made sure the connector was fully seated and decided to reset the computer. no change, except that after about 20 miles I got a CEL that I haven't been able to check yet. Any Ideas???????

 

Do the key on 3 times trick and get the code then post back. Also whats nice about that feature is you can do it anywhere and all you need to do is call like autozone and tell them that number and they will be able to tell you what it is.

 

Yeah, only problem with that is that I'm on a boat in the middle of the Gulf of Mexico and my truck is sitting at the dock, LOL. I'm sure the code is something like no signal from speed sensor or something like that but I'm wondering what caused mine to go out if in fact that is what happened. I found out today that the trans did come from another Dakota with a 5.2 and a 3.21 rear end. I wonder if there was some kind of difference about the spur gear on the output shaft that might have eaten up the gear on my speed sensor.

 

any ideas?