03' 6.0...jumped in tonight, truck had been sitting about 6hrs, temp about 40 ish, turned over real slow, then surged (fast, slow, fast ,slow) for a few minutes. Waited for everything to smooth out before leaving the driveway, ABS light stayed on through all that...never behaved like this before, what the ?

 

On my truck when the battery went bad and would almost not start the ABS light would come on. After the next start the light would go off.

Sounds like someone needs new batteries. Remember that you need to replace them as a pair.

 

Checked, cleaned and tightened all terminal connections. Making the difference so far...