A couple of weeks ago my truck started to act weird. My speedometer stopped working,cruise control no longer works, my abs lighht and ebrake light are always on, trans wont shift if i stop too long, engine backfires and battery drains super fast if left connected, even a few minutes. Any ideas?

 

Get the battery and alternator tested. A weak/failing battery can give you all sorts of interesting problems.

Welcome to DF!

 

If it were just abs and brake light on with a speedometer that didn't work until you hit 30mph then I would say it's just the speed sensor on the rear differential but you've got bigger problems than that.

 

The After personal experiences of chasing strange electrical problems I mean really strange ones I have learned to remove clean
and reinstall every electrical ground you can find. Since many systems are being affected it would likely be a major ground, near the PCM, battery and or fuse boxes is where I would focus.

Dodges from the 90s in my area Northeast tend to be as I describe crusty underneath and have many issues with grounds.
Also one good thing is cleaning your grounds is free just takes some time.

Good luck.

 

I had the same problem, but I also had random error lights coming on. My solution was a new ignition switch assembly. $140.00, and a PITA to replace on a 2000 B3500.