I have recently replaced;
Radiator
Water pump
Thermostat
Temp sensor
All hoses
Cap
Reservoir tank
And have done roughly 8 coolant flushes with cleaners to ensure the system was cleaned out and able to flow propetrying?
burped system several times, can't find any more air bubbles.
Guess the only part not replaced is heater core, the heat in truck is working though (not that I need it in florida).

I am attempting to get rid of the clutch fan. I originally put in a cheaper e-fan with no shroud, definitely did not do the trick.

Just put in a "quality" e-fan with shroud from FF Dynamics. It will idle and go around town fine, stays around 190-210 in south Florida 100° weather with air on. This is all well and good. The issue is this truck is going to be used for towing around 6k lbs (boat) and also for off roading/wheeling. Took it off road, after about 45mins of light trail riding with some small wheel spins in sugar sand, had to cut the motor as it was creeping upwards and past 240°. Sat for 20 mins to cool, drove out of the off road area and it stayed around 220-230 on the way out (5-10mins). Get back to pavement and go 30+mph and it came back down to the 200 area.

I'm convinced this fan cannot hold up but want to exhaust all other options first. Is there something I may be missing? I'm aware head gasket could be a problem, but I've got no water in oil, no smoke/water at exhaust... I emailed FF dynamics to get their opinion, as before ordering, they asked location, upgrades, intended use ect and I told them all this. Also mentioned I plan on putting 33s on it and upgrading the motor to around 400rwhp. Yet it won't stay cool at 300 fly hp with 31s on it now.

Opinions? Thoughts? Anything else I'm missing or should try? I really don't want to go back to clutch fan but I'm tempted to order and install one to see if that solves all overheating issues, because if it does I guess that would prove the e-fan just isn't cutting it. That's a 400$ way to prove that though I guess which would be better spent towards the new transmission it's gonna need soon (some first gear slippage, around 135k miles on truck).

 

You need more airflow across the radiator at lower speeds. It's gonna be even worse pulling the boat. What is your truck rated to tow? I would bet that 6K is pushing it really hard......

 

The 96-99 Lincoln Mark8 fan is absolute the best for these trucks - and it's damn near bolt in (have to shave the shroud in 1 spot and make 2 simple brackets). But finding them anymore is getting difficult.

 

it's rated around 6.5k or so, I don't necessarily mean to max it out at 6k and likely going to do a dual axle to help distribute weight even better. Just want this overheating nonsense to stop. Lol

 

FWIW, issue you'll find with boat will be the ability to get up/down a boat ramp without the boat's weight overcoming the holding ability of the brakes/tires on a 4500 pound truck.

I towed my dakota with a uhaul trailer this weekend with the ram 1500. Ram weighs 5500 pounds, uhaul trailer is 1500 pounds, and dakota is 4100 pounds.

5500 pounds towing 5600 pounds was not fun. I can't imagine 4500 pounds towing 6000.

Stick to a 17-20ft boat with a dakota. If you want to have a 25-30 footer or bigger, that's Ram territory.

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All that aside, it's pretty clear the fan is insufficient. Also, clutch fan should only be $50-75 on rock auto I think?

Now also, as I recall, 2000 was the last of the years where the radiator is on the engine side of the core support, and 01+ moved it to inside the core support.

 

Ya I'm looking at the 20' range dual console boats, so more realistically I'll be around the 3-4.5k lbs

but I like doing some heavy wheeling off road as well and need real cooling power for that.

 

What pound cap did you put on? Should be a 20.

Is the cap on the radiator (early model) or on the upper hose (later model)?

 

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Honestly, not sure. I just got whatever cap that advance auto said was for my truck, it's on the upper hose. I did burp the system from there several times to ensure there were no air pockets causing some extra heat.

 

ok, so you have the late model radiator design (which moves the radiator 2" further forward).

I assume you got this kit? https://ffdynamics.com/products/ols/products/dakext8704

I have to assume it uses the 16" 3600 CFM fan. If so, I would think it to be more than plenty, and you're having other heat-exchanging issues at low speed.

Cap should be 20 pounds. It should have the number stamped on the "dot" in the middle of the cap.

What thermostat did you put in it, 180 or 195? Did you drill any holes in it?

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Depending on who you ask and how they measured, the Lincoln Fan flows anywhere from 3200 to 5000 CFM.

https://forums.maxperformanceinc.com...d.php?t=844502

(CFM measured with radiator present)

Stock Ford fan :
High speed
3415 CFM
22 amps @ 12.7 Volts
Low speed
2800 CFM
18 amps @ 13.7 Volts

Dorman :
High speed
3355 CFM
22 amps @ 12.7 volts
Low speed
2578 CFM
16 amps @ 13.7 volts

TYC :
High speed
3116 CFM
22 amps @ 12.7 volts
Low speed
2578 CFM
17 amps @ 13.7 Volts

 

That is correct, that is the fan right there the stage 3 dakota one. That's what the recommended when I told them locale, intended purpose, Intended upgrades ect.

I'll check the cap tomorrow AM, new tstat was a 180°, have not drilled any holes, honestly didnt know that's a thing? I have the fan controller from FF set to kick on right around there at like 185 or so, it's also connected to AC system which today was 96° so the air, and by extension the fan, was on the entire time we were driving.