I replaced the clutch for the engine driven fan on my 01 Durango 4.7 liter with a NAPA part and it is very noisy and it actually feels like the truck does not have as much power and is getting worse gas mileage. Should a new replacement fan clutch be this noisy, or is something wrong?

Sounds defective, should be quiet...


Just my $0.02...

Well parts are sure not what they used to be or should be as far as quality goes. Might try another and if it does the same thing then might want to look into getting one from mopar.

Sounds bad to me. Maybe take it to the NAPA store and let them listen to it before you pull it down, may help your case.

take your tools and replace it in the parking lot. no sense driving off, if the next one is bad too. i went through 3 alternators in a parking lot of a parts store once, before i found one that worked. lifetime guarantee my ass. how do you get a guarantee, when it's dead before you bolt it on?

I knwo on my 99 Durango 5.9 with heavy duty cooling for towing there was a TSB.It was for noisy fan cold.Seems dealer replaced a bunch under warranty.They said it was normal.Its still lous when cold.But a new one if not HD should be quiet.that and it should quiet down after it warms up.Rocky

Factory MoPar not much better,went through 4 in 135,000 on a 4.7,07 Grand.The one it came with off the assembly line was defective.

Aftermarket fan clutches come in different duty ratings for some applications. If you got a severe service clutch it will be louder (locked up) on a cold driveaway, but will be better, albeit still noisier for hot/ high load heat rejection situations.

I went through several standard duty clutches on my Chevy plow truck. It would overheat at 10deg F driving above 45 mph with the plow on. Switched to a severe service clutch and it is noisy as all get out at -10 with the plow, but engine temp never gets above 200.

Fuel economy will suffer with the severe service fan clutch. It takes hp to spin the fan.

My new factory replacement was a bit noisy when cold but settled down in time. Has an electric too so I was glad for that backup.

I went through this on a gen II Hemi Durango. The AZ "torqflow" brand fan clutch sounded like an air boat. Even at -10F that fan was roaring. After returning/swapping it once I went with a MOPAR replacement and it worked properly.

Napa may have sold you a "severe duty" viscous clutch that locks up as low as 180 degrees.

i know that the factory 4.7 v8 viscous clutch contains an internal silicone fluid that is even more "watery" than the 5.9 v8 and allows the fan to slip more so that it turns at a lower RPM and saves a bit of fuel.

i think the FSM says that the factory stock bimettalic coil inside the clutch that locks it up is set for 220 degrees F,
below that it is supposed to slip and fan blade rpm is supposed to be less than 800
even if the engine is at 1000 to 5000 rpm.

Thanks for the replies everyone. By the way, it is now about 4 months old. I don't drive the Durango much (my wife does) so I don't think about it much. After driving it last week though, it was driving me crazy. I think I'll change it.

Guess what? They originally sold me the wrong one. The one I had on the Durango since August was for a Durango with 5.2 or 5.9. No wonder it was killing the mileage.

This got me to thinking though, what would happen if someone would put a 4.7 clutch on a 318 (5.2) or 360 (5.9) Durango, Dakota , or Ram? Would you gain a little better gas mileage? Would it overheat? Inquiring minds want to know.

my memory is fuzzy but i think that i read that when Dodge put the electric fan helper unit on the 4.7v8 version, they then filled the viscous clutch with a lower viscosity silicone fluid that allowed the fan to slip at a lower rpm

there should be a fuel economy gain
especially at idle during weather cool enough
to keep the electric fan off

i have an Oztrip brand fuel consumption meter on my 5.9v8 that measures gallons per hour at idle
i remember that it is about 0.65 fully warmed up
and 0.75 with AC on

i have run without fan blades but cant remember what the idle consumption dropped to right off

Silicone brake fluid is perhaps the easiest fire resistant fluid commonly found.
Perhaps its viscosity is lower than common factory fill of Dodge viscous clutches?

if it is one could blend a fluid to bring the RPM down to custom levels....

I would expect a slight (barely measurable?) gas mileage benefit and it would only overheat sometimes (!). A long standstill on a hot day with AC running would be worst. Personally I like adequate to slightly overkill cooling. I'd stick with the factory designed clutch.