I have a 04.5 with 300k on it. Lately it seems the clutch fan doesnt kick on unless I have the A/c turned on and then only at an idle. It will run high 190s-210 loaded. I get in traffic and kick A/C on and it will cool down to 178.
Just replaced the cap, has a 180 thermostat, radiator, inter cooler, condenser is clear/clean. Awhile back I had seen a thread on hooking a switch to turn the clutch fan on when needed, yet am going cross eyed to find it to tell me what wire(s) to tap into and what to do with it to make it work at speed. Anyone in the know on how to put a manual switch on this or what may be the problem I have?

 

You can put a switch from ground to pin 1 of the fan clutch I think it's green on the clutch side of the plug and brown with a orange stripe on the engine side,plug is down near the crank on drivers side.I put one one mine this weekend and the clutch won't lock immediatly like a AC clutch and it will set a engine code according to the trouble shooting guide in the Dodge manual.Be advised that the above colors are off the top of my head as I don't have the prints in front of me.I did try it in the shop and it did lock up but is slow to lock /unlock also and draws lots of engine power.There is a chart for rpm/fan rpm in the book,I do remember it's not a 1-1 %.Good luck

 

Haven't had chance to get into the plug yet. Last night it ran, loaded like the fan was locked up till 6th gear and ran good temps-185-187) loaded today same material and had to turn heater on just to keep it @ 200 and fan didnt act like it locked up until I got home and turned A/C on then it locked. What book are you referring to there? and where might I get one? Did look up electric fan set thru Summit @$550 but not sure if it'll mount with stock fan in place yet.

 

just tried using the green wire on fan side, grounded it with my power probe and got it to kick on @ 176, so gaining on it so far. Now to let it cool down enough to tap into it and wire a switch. thanks for the info, will let know how it works loaded

 

Book is the Chrysler repair manual , when grounding the green wire the fan if good will lock reguardless of temperature.Normally mine comes on 200-210 and temps will fall to 185 or so until the thermostat closes again.
Also my truck is a F350 conversion .

 

FYI - the Flexalite 264 kit will not mount with the factory fan and clutch assembly in place.

 

I figured the flex lite fan kit wouldn't fit with OEM fan assy. in tact.
Good news is, flip the switch with full load when it hit 205 and 20 secs later the fan locked up and brought temp clear down to 172. Did some looking and found a temp controlled switch from Summit that kicks on @ 200 and off @ 185. Going to call on that and order one soon to plumb into the cooling system then wire the clutch fan to that vs. manually flipping the toggle switch and having to run wires, mount switch. For time being I just ran the wires/switch in the cab to see how it was going to work.