I just bought the truck and the idler pulley fan belt was running on the outer edge of the pulley. My mechanic friend said I would lose that belt so I replaced the idler pulley and tensioner pulley and belt. All new for $508 total.
The idler pulley and tensioner pulley are both smooth.
The fan pulley is both grooved and ridged.
The belt wants to walk off and climbs the fan pulley so I put a 1/2 inch shorter belt to try to improve tension.
The belt was just barely getting pressure from the new idler pulley.
It seems better But I have a little bit wobble or sway when I watch the belt on the idler pulley.
It's staying on so far but I wish the belt were running perfectly straight with no wobble.
Do these belts sometimes have a little bit of sway or do they generally run perfectly straight.
Any suggestions would be appreciated.
If it don't hold belts I have nothing.
No belt no truck.