I just replaced my locked up fan clutch and OMG . Felt better the second I started it up. Started easier, idle's better, revs quicker, quieter, and it feels like I just picked up 20HP due the eliminated parasitic loss! I am curious to see what this does for my gas mileage as well.

 

I just recently trashed the fan and clutch all together and installed and electric unit. Wish I could say I gained 20HP but it is only a 22re. The improvement was still huge! Even a few extra miles on a tank.

 

How can you tell if it is bad?????

 

Where did you get the replacement from and how much was it? I need to replace mine or do the Taurus fan mod. So I am trying to guage price's.

 

Try the following (by hand):

Engine cold: Spins with difficulty, fan roars at start up
Engine warm: Fan spins freely by hand
Engine hot: Fan will not spin and fan roars as idle is increased

 

Can anyone explain how this works? Christian, I tested mine yesterday. Hot and Cold. They seem to have about teh same resistance when hot or cold. When you first shut it off it will spin a little bit (when hot). Let it sit for about 5 or 10 minutes and then it feels more like it's cold. It won't free-wheel. You can spin it by hand, but when you let go of it, it stops, almost immediately. I just don't understand mechanically how it works, and if I did, I think I could figure out if it's bad or not. It roars on startup, both when hot and cold...

Does anyone else hear it start roaring (kicking in) when idling around offroad or while sitting still for long periods of time? I don't.

 

Mine is "roaring" almost all of the time when the outside temp is above 50* so I am certain it is bad. Just need to replace it.

 

So when they go bad they lock up and turn at high speed all the time? Because I am/was (replaced thermostat, but haven't "tested" truck yet) having troubles with overheating, and I notced the fan wasn't "roaring" like it ought to be if the truck was getting as hot as it was... or so I thought.

 

My understanding is that the 5VZ fan clutch works with fluid. As the fluid heats up, the clutch engages and the engine has to turn the fan now (the roar). But that doesn't really explain the cold roar at start-up, so I could be wrong. I should pull one down from the attic and take a closer look. Maybe I will do that this afternoon.

 

It will roar when it is cold because the fluid sitting at the bottom. after you get around the corner it should not. I had to replace mine because it would stay on at highway speeds. Don't buy the autozone, advance, fan clutch. They are made for hevy duty use and they will stay on forever (I know this because I tried them when my fan clutch was bad). I bought the a toyota asin fan clutch on line for about $65.00 . It works great.