I got a 1993 GMC Sierra 454 Crew Cab Duelly. My big white beast is always testing my patience. Just noticed recently that the engine compartment gets extremely hot, so hot that the fenders are hot. My husband was thinking that the radiator fan needs to be replaced but the truck does not overheat. Heat actually radiates into the cab. He says the electric fan just free spins and thinks it is not working, the clutch fan work fine.

So does it sound feasible to need to change the electric fan or is there some fuse that may need to be replaced?

So far my girl has had to have the tranny replaced, whole front suspension replaced, most of the electrical replaced, fuel pump is sitting in my other truck waiting to be put in. She only has 134,000 miles on it and runs great, when she runs.

 

My old 89 pickup with the 305TBI engine and my 96 with the 305 Vortec both did this, I don't know if you have ever had the grill off your truck, but the radiator is mounted to the front of the truck and can contact the radiator support acting as a heatsink. I found it to perfectly normal to find my fenders hot after a good drive, just because the radiator is transferring heat into the metal surrounding it.

 

If you tow a heavy load with a lot of hills does it seem to overheat at all?

 

No it never overheats, just gets hotter than hades under the hood, fenders, firewall and even the floor of the passenger area get warm. Great in the winter because your feet are always warm but really sucks in the summer when the last thing you want is hot feet.

 

Maybe your Catalytic converter is ready to go ... if they get plugged up, they tend to create boatloads of heat.