My truck frequently sounds like an airplane about to take off from the fan. That has to be sucking a lot of power to push that much air and I'm told that serpentine belt life is short. The noise is also annoying.





Anyone tried an electric fan setup? I was looking at one from Flex-a-lite. It looks interesting.

Bobt250;


The electric fans move much less air than the engine driven one. Some guys have gone to a Duramax fan they will bolt on if you have a 20 inch 9 blade steel fan they are quiter than the steel ones. If you go the Duramax fan route you may need to trim the fan shroud a bit for clearance as it's 21inches. When is your fan coming on real regular? If it comes on and your not towing you may have to clean you cooling system. Every couple years you should remove the raditor have if clean and checked for leaks, I did mine and the shop charged $25 I felt like a theaf that included fixing 2 small leaks. Also between the raditor and A/C condenser bugs and dirt and leaves and stuff collects and cuts cooling. It made a big difference.Edited by: 16gaSxS

I like the eletric fan idea. I would use a temp. controlled relay to run it so it could cool down the radiator while the truck is off. I would also want to be able to switch it off from inside the cab(for low water crossings).

Mostly it is worse when it is cold. I think the oil in the clutch is cold and thick. It's not because it's actually hot.





The Flex-a-lite fan says it moves 5500cfm. What does the stock fan move?

The stock fans move about 10,000cfm at 3000rpm with clutch engaged. It sounds like your clutch may need replacing you can get a GM from GM parts Dirrect for about $70 , Kennedy Sells one that come on at a lower temp than stock for $250 and Hayen makes a Severe Duty clutch that many people have had good luck with , Heath sells them for $159. Is your clutch 4 or 6 bolts holding the fan? JK says his is the ONLY one that comes on at the lower temp, and he may indeed be right. A lot of folks swear by it. Also do you have dual or single thermostats on your truck? I live in Montana and have driven my truck in -30 temps and have NEVER had the fan clutch engage when it cold so I would say the clutch is shot.

The stock GM fan clutch has a wide design tolerance for coming on, between 165 and 195 degrees F. Mine tends to be on the lower end of the range and will come on, for about 50 yards, at almost every traffic light when the outside temperature is above 80 degrees. This short duration operation indicates the fan clutc is working and the system has the capacity to remove heat when needed.


If yours has this short duration operation I would consider it an advantage. However if when your fan comes on it remains on for longer durations the system has limitations somewere. The radiator may need cleaning inside or more often the the condinser and radiator may need cleaning outside. Take a look at my site to see just how fast they can fill up with bugs. Make sure what you have is working before changes.