I have a 2002 Dodge Ram 2500 Gas 4x4 with AC. I replaced my old belt because it was a little loose and squealing when I bought the truck last summer. Belt tensioner works fine, but it was at the very limit of it's travel. Brand new top quality belt from Autozone and the belt tensioner was only very slightly more pulled by the belt. IT was ok at first, but only a few months inn, and it's squealing a lot. Belt tensioner is back at it's limit. I see no way to adjust anything else. Only other belts at autzone are 1.5" shorter, and I think that might be too short.

As this truck was modified for plowing by adding extra battery, it make me wonder if he put in a new alternator that is not factory spec and so is lower or something. Everything seems right. Idler pulley is there and working fine.

I need some way to tighten my dang belt! Going around turns at night the belt slips a lot, voltage drops and lights dim.

 

Try the next smaller size belt.

 

for that long of a belt ... 1 1/2 inches is not much. try the shorter belt.

 

Did you replace the tensioner? Also did they give you the right belt? May have different belt for plow package

 

I was going to ask this. How many miles on what I assume is a 360 (5.9 gas) in a 2500? The tensioners wear out over time.

 

Time for a new tensioner (or the right belt).