did you check to make sure there wasn't a break in those wires going to the rear speed sensor (the one you changed)

 

i fallowed it as far as i could and saw no break, if it was broke wouldnt my speedo not work though?

 

it would still work. your gonna need a digital voltmeter and do a continuity test on teh wires.. jumper the 2 wires together at the sensor and then follow the wires all the way to the front of the truck and test them there.

 

check all the plugs for the abs mine came on earlier this week and i found that the passenger side plug bellow the turbo came unplugged. plugged it in then no more light abs worked

 

wouldnt that be for front abs? i thought the only one i had was in the back, no front abs. ill try the continuity test maybe tomarrow if i have time. im kind of worring it might be something worn with the wires under the dash, had alot of electrical problems with the truck when i got it, that of corse i wasnt told about!!!! already spent around $1500 on just getting that all fixed, imagen what i could of done with that money!!!