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Electric fan on Ranger


Krittro Campbell
I have a 91 ranger 4.0. It always runs hot in traffic (235-250 degrees). It runs cool at cruising, but below 35mph it heats up, quick. I have already killed an engine due to it and do not need to go through another. The waterpump, radiator(big one), heater core, hoses, and thermostat(180 degree) are all new.

I was wondering if any of you have put an electric fan on?
What kind?
Did you use special brackets or just the universal ones?
Did you have it runing all the time the truck was or was it switched with a thermocouple?
What size (inch and cfm)?
Do you think if I put a pusher fan behind the grill to compliment the factory pulling fan it will help out much?
Do you know where to find a 200amp alternator for a 4.0 or a bigger than stock amperage?

I am really thinking about the swap but I do not want the electric fan to fail or the brackets breaking or anything else that happens during offroad abuse. any info you guys can give wil be really helpful.

thanks in advance



Well-Known Member
im not sure about specifics on most of the stuff you mentioned but i do know that most all of the electris fans can hold up to the off road abuse. I used to work in a buggy shop and some of the rigs had them and they worked after some tough punishment. one recomendation i have is get a fan with stiff blades as some of the flimsy blades can hit the surrounding casing thing and shatter. i think it would be fine to use it just run off of just a regular toggle switch.

its not speeding unless its a triple digit


Well-Known Member
Hey Kritter, have you replaced your fan clutch? For one thing, your plastic fan blades are probably cracking apart, but your fan clutch should also be engaging at that speed/temp and pulling more air through the radiator. We haven't seen many overheating problems with 4.0's on the street, so it shouldn't be necessary to add an electric fan.

Matt Nelson
Team Kwik Racing


Well-Known Member
DITTO on that, I know someone's ranger had the same thing happen to him, he's running a 3 litre though........


Well-Known Member
I think fan clutches only run around 20 bucks and is a quick change. That has to be the problem, and it is a lot cheaper than buying an electric fan to find out thats not your problem.


Krittro Campbell
THe fan clutch (heavy duty) ran $65 with a wholesale account and 2 Ford tools are needed to change the damn thing on the 4.0, one to hold the pully and a 1.5" wrench to spin the nut. I found out the hard way tonight trying to muscle it off with vice grips since not a single store around had any wrench bigger than 1.25". Now I just have some bloody knuckles, pissed off neighbors, and a new fan clutch waiting to be put on.


Well-Known Member
Just replaced the fan clutch ($29.99 at Autozone) on my explorer (4.0) and thermostat (just because) and the cooling problem went away, used large channel lock pliars on the clutch nut. Now can haul ass up hwy 18 to Crestline with air on and does not get very warm. Sounds like the fan clutch is what is up with yours. As for the alternator I am at a loss.

<font color=red>PAT KAPKO</font color=red>


- users no longer part of the rdc family -
It may be the fan clutch but it may not be. When you say it over heats at any speed below 35 mph , what is the engine rpm? If the rpm is low then a fan clutch may not be your problem. If the engine is turning med to high rpm then I would say yes it is the fan clutch. Remember the fan can only turn as fast as the engine ( basicly, not going into pulley size etc....)

Is your radiator a 2 row or 4?? I have a 4 row in my ranger and it has only had cooling problems when the thermostat went out. I am looking at going to an electric fan to gain some extra Hp. Plus they are better in all around performance. But if I were you, assuming you have a 2 row rad., I would upgrade to a 4 row radiator. The 2 row is just flat out to small for that application.



Krittro Campbell
I changed the clutch and it runs all day now at 185-195 with the ac on and in traffic. It sounds like an airplane, but it runs cool. Thanks for all the info guys.