I got a 97 dodge ram 1500 5.2 some times the starter will only crank slowly and just barely start the truck or wont start it. But yet my headlights turn on seem normal not dim same with interior lights. And other times when i start truck will crank over like normal. I tired cleaning battery posts with wire brush. Still the same , do you think it my battery or starter or ingniton switch? Or i have short somewere?

 

Since you already cleaned the battery terminals, clean the rest of the connections as well. (there is a bunch....) Might be the starter thinkin' about goin' belly up as well.

 

Both the starter and battery was replaced about 4 and half years ago

 

Doesn't mean nothin'.

You local parts store should be able to load test the battery, and also do a starter draw test for you. Takes five minutes, tops. That will let you know if either one is bad....