Upgraded fan clutch

Matt

Silver Supporter
#1
Just wanted to post some information on the fan clutch that I got via @Mooseman (thanks mate!).

Those of us that have the crappy EV fan clutch that eventually craps out are better served replacing it with the thermo clutch. But if you look at the description and photos on RA it could cause some confusion, like it did me. Hayden is the preferred brand and there's 2 part numbers, but the 2851, when you look at the pics, doesn't have a harness hanging off it...does it come with one? :confused:

So I reached out to moose and here's the #truth:

The 2851, being thermal, has no harness, which is why you need a tune to turn off the fan codes when you use it.

The 3200 does have the harness because it is an EV.
So, there you have it, just get the 2851 and have the code tuned out and all will be good.
 

Mektek

Well-Known Member
#2
The EV clutch does have some strange operating characteristics - I get people asking "what's that ticking sound?" . Apparently there's a firmware download to eliminate that but I don't want to pay the stealership $90 so I live with it. I don't know how old it is, but it works OK so I'm not going to change it. There's the additional hassle and cost of sending your pcm out to be reprogrammed. So it will cost you much more time and effort rather than just replacing the EV clutch.
 

Reprise

Gold Supporter
#3
Agreed about the 'don't touch till it's broke' part. The issue about replacing same for same is that the replacement E-V clutches often don't last even as long as the OEM did. There are some members on their 3rd / 4th E-V clutch as a result (I don't recall reading / hearing about a 5th).

Since GM even gave up and switched to the thermal clutch at the end of the run, and those clutches last a lot longer (not 'lifetime', but 80-120K mi, IIRC,) I decided to endure the pain / expense of flashing the PCM--and it's an opportunity to put some 'tuning' in it at the same time. Kinda like the old Bendix/Autolite ads - "pay me now, or pay me later'. Oh, and no more issues w/ people thinking you've got an alarm clock or a bomb under the hood...lol.
 
#4
Some time in the last few years hayden dropped the lock temp of the thermal clutch to 170ish degrees. Because of this on a 75+ degree day if you're running A/C your fan will pretty much constantly be locked up. It is annoying more than anything but my truck runs cool and the ac spits icecubes.
 
OP
OP
Matt

Matt

Silver Supporter
#5
I replaced my EV clutch with another EV clutch about 3 years ago and now I'm getting a P1484 code, hence why I'm going with the thermo.
 
#6
So, Im doing the same in the next few weeks, getting a small surgery done, then back to work, A guy at work says you can get the clutch out with removing the shroud. I replaced the water pump using the same trick. You take out two bolts from fan to clutch, then put in 2 longer ones, like 3 inches maybe, then take the other 2 OE bolts out. that should let the clutch hang forward, but not hit the radiator, and the shaft at the back can clear the water pump pulley. then just pull fan out. Its really tight on ex cam side. but I don't mind trimming the shroud a bit if I can do it faster and not open the coolant system.
 
#7
It is not likely that you will get the clutch out without removing the shroud. If he can do it I want to see it documented. Some of us have been with this platform for a long time and I have not seen a clutch replaced without taking the shroud out.
 
#8
It is not likely that you will get the clutch out without removing the shroud. If he can do it I want to see it documented. Some of us have been with this platform for a long time and I have not seen a clutch replaced without taking the shroud out.
:2thumbsup: Challenge accepted, I'll give it a go, he said it should take less than an hour. What's worst that could happen? I break my own car.
 
#9
I can take the shroud and fan clutch off and replace the water pump in less than an hour.
 
#11
The hayden clutch is a lot shorter than the ev one. If I bust the fan free I can squeak it out as long as i loosen the shroud... for the extra 10 seconds it'll take though just pull it.
 

Mektek

Well-Known Member
#12
"Some time in the last few years hayden dropped the lock temp of the thermal clutch to 170ish degrees. Because of this on a 75+ degree day if you're running A/C your fan will pretty much constantly be locked up. "

That would be a good reason not to go with the hayden thermo clutch. If you are in a hot climate where the temperature is usually above 80 then the clutch will be locked most of the time and your engine will sound like a tractor trailer and will have lower fuel economy.
 
#13
I have two. One is a Hayden, the other a 4 Seasons. Except at startup, neither get locked up. They might pull more at idle if it gets hot enough but do variate speed as they should.

I haven't heard neither ever lock up while moving. Might have spun a little harder at idle but that's about it.
 
#14
I have two. One is a Hayden, the other a 4 Seasons. Except at startup, neither get locked up. They might pull more at idle if it gets hot enough but do variate speed as they should.

I haven't heard neither ever lock up while moving. Might have spun a little harder at idle but that's about it.
Mine sounds like a semi after running for a few minutes. Sustained highway driving is actually a little annoying. Quick google shows it is a relatively normal occurence. Think I should try another one. Problem was I did the swap in the winter so it took 5 months for it to start happening.