Yes normally it comes with a harness that has two relays for the high and low speeds. I got mine from a pick-n-pull and it looked like someone had already grabbed the wiring harness and left the fan. It didnt really matter to me though because I pulled the plug off the stock A/C fan and wired it onto the Volvo fan wiring so it plugged right into the OEM wiring. This worked perfectly fine and the OEM wiring controlled both low and high speeds.



I used TorquePro with the Jeep's profile set to use OBD2 protocol ISO 9142-2. I use a OBDLink LX unit for the bluetooth. It does still get booted from time to time but generally will stay connected long enough for me to get most datalogs without issue.



I've actually become a bit leary of the FFD's fan claims since I've done some research and looked at other fans made by reputable brands. I'm sure they are decent fans but I am seriously doubting that their FFD3600 can actually flow 3600 CFM. The reason I think this is because they only use and 18 Amp motor and other manufacturers are using 24 and 28 amp motors on similar fans and only getting 2/3 of the CFM's. Spal's VA33 16" fan draws a whopping 28 amps and only sees 2000 CFM, Derales 17" HO fan is 24 Amp and 2400 CFM. Either FFD has some magic fairy dust or their claims are stretched in my eyes.

My dad actually just installed a set of spal 12" fans on his trailblazer supersport and they are beasts. They can cool a 400+ HP LS2 Just fine so I wouldnt be afraid to run the same setup on the Jeep. There are guys running 600, 700, 800 hp with those fans even.



I got mine to fit but the shroud I made had to fit flush with the back of the radiator tanks and that gave me a solid inch of space. My first shroud attempt put the front of the fan about 1/2 to 3/4" off the back of the radiator tanks and the very back of the fan motor was touching the stock fan pulley. The actually radiator core sits something like 3/4 of an inch in from the back of the tanks so the flush mount shroud still has a good air gap.

Unfortunately, right after I got the fan and shroud installed and working, the fan self destructed on the first test drive. It worked great in the garage. The factory A/C fan wiring was able to trigger both high and low speeds for coolant temp and functioned for A/C duties as well, but I took it down the road and one of the blades fractured and it came apart. I got the fan from a Volvo that had rolled so I am thinking maybe it had some damage I never saw.

Anyways, the way I built the shroud is such that its semi modular, so I can install different sized fans just by replacing the back. After the fan blew up I went out and bought this unit http://derale.com/products/electric-fans/universal-electric-fans/high-output-single-rad/straight-3-8-npt-female-x-3-8-barb-fitting-detail since it is also a 2 speed motor and is a massive 17".

I plan on doing a write-up once I get it installed and working and can test out the performance. Unfortunately the weather here in Utah is getting cool already, like low 70's during the day and 40's at night, so it wont stress the cooling system too much anyways.

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2006 CRD - GTB2056 turbo by Dieselguy86, Eco Trans Tune, Lift Pump, Week's, HDS Tstat, Racor Filter, ARP's, OME 790's+Top Plate, JBA 2.5", JBA UCA, Moab's+265/75R16, ARB Bull Bar, 4.10's, TrueTracs

Been out for a few months, but wanted to add to this thread that I've been towing 7k pounds over a good mountain grade with the FFD fan, and HDS stat (203 degree) in warm weather (probably up to 90 degrees F) with zero overheating. No AC, lifted CRD with stock size AT tires.
So, in short, it looks like the electric fan is a viable alternative to the mechanical fan. I do take it easy towing heavy loads over grades (49mph 1900 rpms), and haven't tried when it was 100 degrees yet. If I had to tow 6000+ lbs over big grades in the rockies at 100 degrees often, then I'd probably run the mechanical fan...

Oh, I also have an almost new top end (head, cams, rockers. I think rockers with 100k+ miles on them might not move the heat out as well.

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05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

FOLLOWING...

An aggressive fan like the 11 blade GM plastic fan with a clutch is one of the MOST EFFECTIVE cooling options for an engine with a cooling system that is somewhat "marginal" by design from the factory to begin with. I don't have the CFM ratings, but a few years back I remember one of the car magazines did an article on mechanical vs electric fans. I remember the ratings of a large clutch fan was about three times that CFM flow rating that of a comparable large electric fan.

A cooing fan on a vehicle is not doing much work at speeds above about 30 mph. Anything above about 30 mph and there is enough forward pressure on the front of the radiator (assuming normal airflow) to move more air through the radiator than most fans are capable of, mechanical or electric. The low pressure zone under the vehicle causes the engine compartment to evacuate and a fan actually becomes secondary due to the hydrodynamic principle.

The simple truth, you can't move more air through a radiator core than the space between the radiator fins and the density of air will allow. You normally exceed this at road speeds. The purpose of any cooling fan is to maximize air flow at low speeds especially during in town stop and go driving or when the engine is working very hard and producing lots of heat. Low speed driving is where a much more efficient cooling fan like the 11 blade GM fan or a comparable size electric fan can really make a difference especially if you are driving in 100+ degree ambient air heat along with very high humidity. The Jeep CRD by design already has an electric fan on the front side of the radiator stack to help supplement cooling at lower speeds.

I can tell you for a fact that in my case adding the 11 blade GM fan to my Jeep Liberty CRD certainly helped to greatly improve the performance of the AC during hot summer 100+ degree & high humidity conditions when driving in town during stop and go driving. Engine cooling probably was improved as well, but I was not having any engine cooling issues, only AC performance issues at lower speeds. Swapping out the metal OEM fan for the 11 blade GM fan was the easiest and least expensive option with the least headaches as opposed to having to deal with the location, mounting issues, and figuring out all the wiring, relays, and command and control processes involved with adding an additional electric fan. An electric fan at best can at least match a mechanical fan at idle speed.

And then there is the other big part of this (elephant in the room) which certainly factors into any discussion when it comes to engine cooling, and that is the engine cooling system components themselves and their respective relational performance.
Radiator conditions both inside and outside the core, water pump, thermostat operation, and engine head or head gasket leakage issues.

Just remember: No matter what you do or add to a cooling system, it will never perform any better than its weakest component!

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Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve