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Discussion Starter #1 (Edited)
I think my fan clutch may be shot. I can rotate it by hand when the engine is off, but it's pretty stiff. It doesn't free-spin. It blows air when the engine is running, but never seems to do a full lock-up and make a roaring sound. I ran the truck up to operating temperature and turned the AC on and off at idle and nothing. I never hear the roar of the fan being fully engaged. In fact, I can't remember the last time I heard it, so it's been a while. Last summer, the AC wouldn't blow cold air at idle. Freon level was low so I added some and its a little better. Wondering now if it was really a fan clutch issue, not cooling the condenser.

So far I've checked the plug and wiring. It's all there and hasn't been cut by the fan. When I get a few minutes I'l run an Ohm test on the plug to see it it checks out.

I'm still running the original fan clutch so I'm probably due. The online prices I'm seeing are shocking (around $400.00 for the part) so I'm looking for a less expensive source. I'd like to stick with the OEM but the pricing is beyond ridiculous. Does anyone have a source to pick up one for less. Any tips on diagnostics before get I too much further into this?
 

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I can rotate it by hand when the engine is off, but it's pretty stiff. It doesn't free-spin. It blows air when the engine is running, but never seems to do a full lock-up and make a roaring sound. I ran the truck up to operating temperature and turned the AC on and off at idle and nothing. I never hear the roar of the fan being fully engaged.
I have my truck for more than nine years and put over 150K miles on it myself.
I noticed everything exactly the same as you described above.
I never towed.
I never have issue related to fan clutch operation so I never think my fan clutch is defective.

The fan clutch engagement and degree of engagement are determined and controlled ECM.
ECM considers some variables like coolant temp, AC high side pressure ........etc and send PWM signal to the fan clutch.

For coolant temp it's over 215F for the fan clutch to kick in.
When the AC pressure increases above 240 psi the fan will kick in.

What's your current issue?
If it's AC related I would recommend to check the refrigerant level first.
It probably doesn't need the fan clutch to engage when idling with AC on.:wink2:
 
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Discussion Starter #4
Thanks for the response PWONG. I questioned what normal operation is as well. Current issues are:

AC is marginal at idle but working a little better since I added freon last summer

Transmission fluid temp. Before adding a Dynamic transmission cooler delete kit and later a new Mishimoto transmission cooler, transmission always ran hot in the summer. When running empty, 200 -215 was normal around town on my Edge Insight gauge (which reads 15 degrees F too high). During slow climbs in the mountains pulling a light ATV or raft trailer, It quickly got up to as high as 230. Always feel like I have no buffer for serious hauling on a hot day. New cooler is doing much better with thermostat deleted. All radiators, coolers are clean and fins straightened.

Coolant temp is running at 200 degrees F on gauge now with normal driving. Used to be steady at 190.

I have a back country trip planned that will put a strain on the cooling system. It's 100 miles of steep, narrow, sometimes rocky, switch back climbs to 8000 feet. There are slow climbs to old lookout towers where the speeds will be closer to 10 mph. There are no services for the duration of the trip. Average speed will be around 20 mph so not much wind going through the radiator. See: https://www.fs.usda.gov/recarea/nezperceclearwater/recarea/?recid=16482

Right now I'm prepping the truck for the trip, everything from tires and brakes to cooling systems.
 

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cerberusiam has posted several times that his users have had good luck with one brand of aftermarket fan clutch for the 3rd Gens diesels. Believe it was NAPA or Autozone, check with cerb.

NAPA is about half the price of the OEM.

Flip the AC on MAX cool while working the motor hard at low speeds, will at least get some lockup and extra cooling starting at lower temps.

Have you tried a coolant system flush with Fleetguard Restore or use Restore Plus if not done for years. These Cummins iron blocks scale up heavily reducing cooling. Scale also plugs the block/head cooling passages, hoses

Slipping fan belt or slick pulley from oil or use of silicone spray under hood will also decrease the cooling efficiency, fan and pump both slip.
I've used 100 grit sand paper to roughen them up to increase grab.

Great trip in the backcountry. got your EPERB?

Take a gun, grizzlies think Dodge Rams are food frigs with nice plump human eats inside
 

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ECM reacts to coolant temp when it’s above 215F.
The transmission temp should be reflected by the coolant temp for a stock transmission cooler which an heat exchanger between trans fluid and coolant.

Not sure whether ECM will reacts to transmission fluid temp directly.

The fan clutch can be actuated/fully engaged by grounding (= 100% PWM signal) the control signal to clutch from ECM.
If you have a way to read the fan rpm you can run the engine at different rpm and measure the fan rpm to see if it works according to a table.

Please refer to the FSM for details of test.
 
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For the AC issue I wouldn’t blame the fan clutch until I see the high side pressure is above 230psi.

Should verify the the AC system performance with manifold gauges before condemning the fan clutch.

Any fan clutch DTC?
 
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Discussion Starter #8
No codes on Edge CTS

For the AC issue I wouldn’t blame the fan clutch until I see the high side pressure is above 230psi.

Should verify the the AC system performance with manifold gauges before condemning the fan clutch.

Any fan clutch DTC?
Haven't seen any fan clutch codes on my Edge CTS. Will try with another scanner to see if something pops up. I don't have any AC test equipment so I may have to bring it by a shop to get the system checked. I've read that excessive high side pressure caused by a non-working fan clutch can take out your compresor, so a test is in order to make sure both systems are operating correctly.
 

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Discussion Starter #9
Aftermarket fan clutch

cerberusiam has posted several times that his users have had good luck with one brand of aftermarket fan clutch for the 3rd Gens diesels. Believe it was NAPA or Autozone, check with cerb.

NAPA is about half the price of the OEM.

Flip the AC on MAX cool while working the motor hard at low speeds, will at least get some lockup and extra cooling starting at lower temps.

Have you tried a coolant system flush with Fleetguard Restore or use Restore Plus if not done for years. These Cummins iron blocks scale up heavily reducing cooling. Scale also plugs the block/head cooling passages, hoses

Slipping fan belt or slick pulley from oil or use of silicone spray under hood will also decrease the cooling efficiency, fan and pump both slip.
I've used 100 grit sand paper to roughen them up to increase grab.

Great trip in the backcountry. got your EPERB?

Take a gun, grizzlies think Dodge Rams are food frigs with nice plump human eats inside
If I end up needing a fan clutch, I'll definitely take a look at the aftermarket stuff. Still working through the diagnostics. Most of the online forums say stick to the OEM part due to high failure rates. Never tried a coolant flush in this truck. Did change the coolant a couple times while doing other work. Might be time. I don't carry a EPERB. Thought about buying something cheaper like a SPOT for backcountry trips but haven't bought one yet. I do file a flight plan and expect there will be others on the road. It's a short 3 month travel season so there will be some pickups, jeeps, ATV's, motorcycles, etc. out there. Biggest fear is meeting people on a one lane shelf road with a 1000 ft drop off and having to back up a mile for a turnout. We only have black bears in the area so far, but grizzlies are migrating in this direction. More than enough wolves, black bears and cougars though.
 

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cerberusiam has posted several times that his users have had good luck with one brand of aftermarket fan clutch for the 3rd Gens diesels. Believe it was NAPA or Autozone, check with cerb.

NAPA is about half the price of the OEM.

Flip the AC on MAX cool while working the motor hard at low speeds, will at least get some lockup and extra cooling starting at lower temps.

Have you tried a coolant system flush with Fleetguard Restore or use Restore Plus if not done for years. These Cummins iron blocks scale up heavily reducing cooling. Scale also plugs the block/head cooling passages, hoses

Slipping fan belt or slick pulley from oil or use of silicone spray under hood will also decrease the cooling efficiency, fan and pump both slip.
I've used 100 grit sand paper to roughen them up to increase grab.

Great trip in the backcountry. got your EPERB?

Take a gun, grizzlies think Dodge Rams are food frigs with nice plump human eats inside
hayes was the one he mentioned...


mike, fan clutch test in the manual states it can take ip to 15 minute sor the fan to engage, seems like a design defect if it actually took that long but worth mentioning...
 

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I've read that excessive high side pressure caused by a non-working fan clutch can take out your compresor.
No.
This is not true.
The safety valve on compressor should operate/open to release the excessive pressure.
I think the ECM also disengage the ac clutch. I just don’t have the pressure number with me now.:wink2:
.
 
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If you have HP tuner module, you can see what the ECM is commanding for the fan vs what is actually doing. It is a very good diagnostic tool for other systems on your truck as well.
 

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Discussion Starter #13 (Edited)
Fan clutch engagement parameters

hayes was the one he mentioned...


mike, fan clutch test in the manual states it can take ip to 15 minute sor the fan to engage, seems like a design defect if it actually took that long but worth mentioning...

Was it Hayes or maybe a Hayden like this one (Hayden 3282)? https://www.haydenauto.com/en/ecatalog?year=2005 There's some speculation that Hayden might even make the OEM version.

I recall reading about the long wait time for the clutch to engage and had the same feeling. Seems like a poor design to let things keep heating up. I let it run for about 5-10 minutes at full operating temp, at idle, with AC on full blast. No engagement or fan roar. The ECM temperature thresholds to trigger fan engagement seem a bit high. Work stuff and an insurance claim has kept me from from further diagnostics today. We had a big storm here a few days ago that dropped a pretty big Ponderosa Pine on the house. Got it removed and now working on the estimate to get the roof repaired.
 

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Discussion Starter #14
That would be very handy

If you have HP tuner module, you can see what the ECM is commanding for the fan vs what is actually doing. It is a very good diagnostic tool for other systems on your truck as well.
I don't have an HP tuner module. I also read that a bi-directional scanner will command fan engagement to verify operation. I'll be under my truck on a creeper with a multi-meter and a jumper wire. Old school baby!!!
 

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Was it Hayes or maybe a Hayden like this one? https://www.haydenauto.com/en/ecatalog?year=2005 There's some speculation that Hayden might even make the OEM version.

I recall reading about the long wait time for the clutch to engage and had the same feeling. Seems like a poor design to let things keep heating up. I let it run for about 5-10 minutes at full operating temp, at idle, with AC on full blast. No engagement or fan roar. The ECM temperature thresholds to trigger fan engagement seem a bit high. Work stuff and an insurance claim has kept me from from further diagnostics today. We had a big storm here a few days ago that dropped a pretty big Ponderosa Pine on the house. Got it removed and now working on the estimate to get the roof repaired.
Ouch, sorry to hear about the tree! no one hurt?

yeah hayden, not hayes sorry, brain fart
 

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A replacement 98 ford diesel mechanical fan engages with no delays at 206F and your back to 195F in 30 seconds. The AC is always cool and no connector to worry about. A poor connection to the fan shuts down the AC as will a poor connection at the connector below the compressor. I had so many problems with the latter I hard wired it. There is a pressure sensor above the compressor with a connector that can also cause problems. Check for a low fan speed code.
 
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hayes was the one he mentioned...


mike, fan clutch test in the manual states it can take ip to 15 minute sor the fan to engage, seems like a design defect if it actually took that long but worth mentioning...
I think it can take up to 15 minutes to finish the transfer of viscous fluid between chambers from fully disengaged state to fully engaged state.
During normal operation ECM will not jump from 0% to 100% engagement in one step.:wink2:
 
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And I'm still thankful I went the Mod route, No guessing or wondering why it will or won't work. Almost 3 years and going strong with great AC, even at idle.
 
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Just being curious, how are you mod guys handle the fan clutch DTCs and CEL if there is any?

Years ago a did a mod on my big Bronco with a Taurus electric fan and noticed that it hurt the mpg and I didn't like it.
 
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No.
This is not true.
The safety valve on compressor should operate/open to release the excessive pressure.
I think the ECM also disengage the ac clutch. I just don’t have the pressure number with me now.:wink2:
.
The high side pressure number is 460 psi.:wink2:
 
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