The speedometer in my 1st gen 1996 3.9L does not work and the automatic transmission plug looks like this, my plan was to replace the wiring harness but I don't believe this is factory and can't fine anything similar
I believe that is the speed sensor wiring. I have a 95 & it has the same set-up. It is an upgrade over the factory one, which they had some kind of problem with, so they up graded them with this. It goes between the speed sensor on the transmission & the harness coming from the truck, I believe. I got mine from Rock Auto if that helps.