Should you get a heavy duty fan clutch?

[machoheadgames]

I much prefer the 4 bolt fan clutch as it doesn't require a specialized tool to hold the water pump still. I put the Hayden on my 99 that was equivalent to the 2771 "heavy duty", and always noticed how much louder it was, but it didn't bother me quite as much on that one because it helped conceal an annoying lifter tap.

The USMW for the late model (1 large nut instead of 4 small) is on Amazon but shows out of stock so I ordered it from Rock Auto. I'm building quite a collection.

I find either have their quirks. The 4 bolt likes to get stuck on there and takes considerable wiggling to remove. I have slammed the fan into the radiator before due to the wiggling and it finally coming loose.

The “heavy duty” 2771 has one appearance, the USMW has a different appearance and is marked as standard duty. All of the heavy dutys despite what brand they are look the same, and then the standards all look different from HD the same amongst themselves too.

I just wish Mopar could still be bought. But I think USMW is the way for me to go. Being marketed as standard duty I imagine it should be plenty quiet.

I have been reading this thread too much. When I say 2771, I keep thinking that’s the old style. I meant the 2737, which is the 4 bolt equivalent of the noisy HD 2771 spin on.

 

[Zorba]

I just, and I mean *JUST* got back from a short test drive with the new 2771 I just popped in. Based on that short drive, it seems that the fan doesn't spin down until its run at about 3K RPM for a bit, and will start up again when RPMs drop to near idle. More testing is needed, I'm going to drive it to a Belly Dance party in about 45 minutes and see how it does on the highway, etc.

BUT - based on this meager data, if that fan runs more at low RPMs, I'm just *FINE* with it. Temp gauge stayed below 210, which it didn't before - I'll see what happens on the drive to the party.

 

[Zorba]

Update of sorts. Clouds blew in, so it cooled of considerably, so I wasn't able to get a real test. With that said, it seems that the fan runs more under about 2,700 RPM or so. *shrug*

 

[freedom_in_4low]

I just took my first drive with the USMW fan clutch and can say my search for a fan clutch is over. It started engaged out my driveway but it disengaged and went quiet about 50 yards down the street. I was on a grocery run, and it got up to operating temp and I heard the fan more when I was crawling around in the parking lot, but it never got to the point of being obnoxious like the Hayden models.

Here's the side by side comparison with all 4.

Clockwise from the top left - USMW, Hayden Heavy Duty (2771), Hayden Severe Duty (2791) which also looks identical to new Mopar, and original Mopar made by Delphi.

Goes to show you can't judge a fan clutch by the housing, because if anything the USMW most resembles the 2791 but has a completely different engagement profile.

At any rate, I now have a Hayden 2771 and 2791 that I don't have use for. I'll at least wait until I have a 100+F drive on it USMW and make sure the temperature does ok but barring anything unexpected I'll put the Hayden's up in the parts for sale section.

 

[machoheadgames]

I just took my first drive with the USMW fan clutch and can say my search for a fan clutch is over. It started engaged out my driveway but it disengaged and went quiet about 50 yards down the street. I was on a grocery run, and it got up to operating temp and I heard the fan more when I was crawling around in the parking lot, but it never got to the point of being obnoxious like the Hayden models.

Here's the side by side comparison with all 4.

Clockwise from the top left - USMW, Hayden Heavy Duty (2771), Hayden Severe Duty (2791) which also looks identical to new Mopar, and original Mopar made by Delphi.

View attachment 447945


View attachment 447946

Goes to show you can't judge a fan clutch by the housing, because if anything the USMW most resembles the 2791 but has a completely different engagement profile.

At any rate, I now have a Hayden 2771 and 2791 that I don't have use for. I'll at least wait until I have a 100+F drive on it USMW and make sure the temperature does ok but barring anything unexpected I'll put the Hayden's up in the parts for sale section.

Good stuff! Hope it works well in the 100°s, if so I’ll for sure be buying the flange equivalent version.

 

[Danarch]

I just took my first drive with the USMW fan clutch and can say my search for a fan clutch is over. It started engaged out my driveway but it disengaged and went quiet about 50 yards down the street. I was on a grocery run, and it got up to operating temp and I heard the fan more when I was crawling around in the parking lot, but it never got to the point of being obnoxious like the Hayden models.

Here's the side by side comparison with all 4.

Clockwise from the top left - USMW, Hayden Heavy Duty (2771), Hayden Severe Duty (2791) which also looks identical to new Mopar, and original Mopar made by Delphi.

View attachment 447945


View attachment 447946

Goes to show you can't judge a fan clutch by the housing, because if anything the USMW most resembles the 2791 but has a completely different engagement profile.

At any rate, I now have a Hayden 2771 and 2791 that I don't have use for. I'll at least wait until I have a 100+F drive on it USMW and make sure the temperature does ok but barring anything unexpected I'll put the Hayden's up in the parts for sale section.

Thanks for the info. I just ordered the Hayden 2771 two days ago. Since I bought the LJ and has 112K on it just decided to replace the water pump, thermostat, and fan clutch. Hopefully I won’t be disappointed by the noise. I am a little confused as some stated they prefer the 4 bolt instead of the big nut, but it seems all four of these have 4 bolts and one large nut in the middle.

 

[machoheadgames]

Thanks for the info. I just ordered the Hayden 2771 two days ago. Since I bought the LJ and has 112K on it just decided to replace the water pump, thermostat, and fan clutch. Hopefully I won’t be disappointed by the noise. I am a little confused as some stated they prefer the 4 bolt instead of the big nut, but it seems all four of these have 4 bolts and one large nut in the middle.

99 and older have a 4 bolt flange to bolt to the water pump. All of them have a 4 bolt pattern for the fan to bolt to the clutch.

2000 and up switched to a large threaded nut to thread onto a large stub on the water pump. They retained the same 4 bolt fan pattern and the same fan blade design itself though.

 

[Danarch]

99 and older have a 4 bolt flange to bolt to the water pump. All of them have a 4 bolt pattern for the fan to bolt to the clutch.

2000 and up switched to a large threaded nut to thread onto a large stub on the water pump. They retained the same 4 bolt fan pattern and the same fan blade design itself though.

So in the picture below the fan clutch attaches to the water pump with the center nut and the other four holes are left empty on a 2006? Then the fan attaches to the four holes in the fan clutch?

 

[machoheadgames]

So in the picture below the fan clutch attaches to the water pump with the center nut and the other four holes are left empty on a 2006? Then the fan attaches to the four holes in the fan clutch?

View attachment 447957

Those 4 holes on the pump are what the pulley bolt to. Still gotta have the pulley.

Fan bolts to the 4 holes on the clutch, yes.

Yes, on that pump the fan clutch threads on the large threaded stub with the clutch’s large threaded nut.

 

[Danarch]

Those 4 holes on the pump are what the pulley bolt to. Still gotta have the pulley.

Fan bolts to the 4 holes on the clutch, yes.

Yes, on that pump the fan clutch threads on the large threaded stub with the clutch’s large threaded nut.

Wasn’t thinking about the pulley. All makes sense now.

 

[freedom_in_4low]

Thanks for the info. I just ordered the Hayden 2771 two days ago. Since I bought the LJ and has 112K on it just decided to replace the water pump, thermostat, and fan clutch. Hopefully I won’t be disappointed by the noise. I am a little confused as some stated they prefer the 4 bolt instead of the big nut, but it seems all four of these have 4 bolts and one large nut in the middle.

It's an early vs late thing. My 99 had the four bolt flange, 06 has the big nut. I despise single purpose tools and I always have a hard time getting the big nut started onto the threads, so I prefer the earlier design.

 

[Zorba]

I'm happy with my new 2771 - yea, it makes more noise, but its only noticeable above 2K and doesn't get "loud" until its close to 3K. People's expectations and driving styles differ, its fine for cruising - it only comes to notice when accelerating. The important thing is that my Jeep is running significantly cooler thus far - and its been hot as balls here. A little noise doesn't concern me. YMMV and all that.

 

[MountaineerTom]

I just took my first drive with the USMW fan clutch and can say my search for a fan clutch is over. It started engaged out my driveway but it disengaged and went quiet about 50 yards down the street. I was on a grocery run, and it got up to operating temp and I heard the fan more when I was crawling around in the parking lot, but it never got to the point of being obnoxious like the Hayden models.

Here's the side by side comparison with all 4.

Clockwise from the top left - USMW, Hayden Heavy Duty (2771), Hayden Severe Duty (2791) which also looks identical to new Mopar, and original Mopar made by Delphi.

View attachment 447945


View attachment 447946

Goes to show you can't judge a fan clutch by the housing, because if anything the USMW most resembles the 2791 but has a completely different engagement profile.

At any rate, I now have a Hayden 2771 and 2791 that I don't have use for. I'll at least wait until I have a 100+F drive on it USMW and make sure the temperature does ok but barring anything unexpected I'll put the Hayden's up in the parts for sale section.

Is that the 22160 standard duty? Curious to see further results.

 

[machoheadgames]

Is that the 22160 standard duty? Curious to see further results.

I think it’s turning out that the factory HD stuff (which is what typically the build sheets refer to the stock 4.0 stuff as IIRC) corresponds well to aftermarket SD stuff. Seems like aftermarket HD stuff is too HD.

 

[Danarch]

I'm happy with my new 2771 - yea, it makes more noise, but its only noticeable above 2K and doesn't get "loud" until its close to 3K. People's expectations and driving styles differ, its fine for cruising - it only comes to notice when accelerating. The important thing is that my Jeep is running significantly cooler thus far - and its been hot as balls here. A little noise doesn't concern me. YMMV and all that.

Well that is my goal, a cooler running engine. It’s primarily a idle thing with the a/c on. I really only notice too because I have and OBDII gauge plugged in with a digital readout. Otherwise the needle doesn’t move much. Who knows when the coolant was changed last so maybe just changing the coolant would work, but figured I might as well change the fan, pump, thermostat while I am at it.

 

[freedom_in_4low]

Is that the 22160 standard duty? Curious to see further results.

Yes, it's the 22160.

 

[chili_pepper]

Since I bought the LJ and has 112K on it just decided to replace the water pump, thermostat, and fan clutch. Hopefully I won’t be disappointed by the noise.

I recently got my LJ with 113k and did everything but the heater core. I also went with the Hayden 2771...you will notice a difference, both audible and in "feel". I'm not saying it's good, bad or better, personal preference I suppose. I will say that I trust the fan clutch is doing the job and I now have full confidence in the cooling system, though I will be watching how @freedom_in_4low makes out with this USMW fan clutch....

 

[Danarch]

I recently got my LJ with 113k and did everything but the heater core. I also went with the Hayden 2771...you will notice a difference, both audible and in "feel". I'm not saying it's good, bad or better, personal preference I suppose. I will say that I trust the fan clutch is doing the job and I now have full confidence in the cooling system, though I will be watching how @freedom_in_4low makes out with this USMW fan clutch....

Thank you for the information. I am hoping for some difference in the cooling, but they may have been able to be achieved by a flush and fresh coolant. Just figured easy enough to do and I’ll know all those components are good. Better at home then on the trail.

 

[machoheadgames]

Went ahead and ordered the flanged USMW for mine. I have little patience.

 

[freedom_in_4low]

Went ahead and ordered the flanged USMW for mine. I have little patience.

Probably not a bad idea not waiting for me. We got a cold front and I'm leaving early Thursday morning for Colorado so I'll be in cooler air before the heat of the day. I don't know when the next time is that it'll see 100+ again.