by "the little coil doo-dad on the switch" you must mean the dropping resistor that allows multiple fan speeds, which would likely mean less heat if all you have is full on/off for the fan ohwell sorry Will, sounds like you've done about all you can, these trucks weren't made for subzero cruising, they were made as workin mens trucks, gonna hafta get the family new parkas for Christmas grin

Bill


Moved over to the Passing Lane

"When we tug a single thing in nature we find it attached to the rest of the world" John Muir
"When we tug a single thing on an old truck, we find it falls off" me
Some TF series details & TF heater pics & Rust-a-holics Unanimous parking lot