Upgraded Fan or Electric Fan

[Valgrind]

Has anyone either added another electric fan to the front of the radiator or replaced the clutch fan with electric fans?

I am in Florida, 95°F day heat, just after 20 minutes of off-roading, both the coolant and transmission temperatures were at 230°F. That made me nervous enough to stop any obstacles and let it cool by driving somewhere faster. Also, temperatures were at 215°F just by sitting parked for a while. Usually, I'm getting 180-190°F transmission and 195°F coolant while driving. I don't think these temps are bad by itself, but I won't always have the option to just stop driving after 20 minutes.

I know a few people have installed other secondary transmission coolers but id rather try the fans first if I can since my problem is slow speed.

 

[bloc]

If your fan clutch is working correctly there should be no need to downgrade to an electric fan.

I say downgrade because there isn't a single electric fan that will fit into our vehicles that can match the air movement of our mechanical unit when it's working correctly. Plus, you'd be paying substantial money for this downgrade, and likely reduce overall reliability. Toyota has kept mechanical on the 200 and 300 while other manufacturers are putting electric fans on their quarter-ton trucks specifically because it has more capacity when needed, in spite of the NVH and fuel economy penalties.

A number of people here tow heavy through very hot conditions and while some have augmented the transmission cooling as you point out, I haven't heard of a need to improve engine cooling.

So yeah, I'd verify belt and tensioner condition, make sure the aux fan is coming on with AC, then consider putting a fan clutch on it.

 

[Valgrind]

If your fan clutch is working correctly there should be no need to downgrade to an electric fan.

I say downgrade because there isn't a single electric fan that will fit into our vehicles that can match the air movement of our mechanical unit when it's working correctly. Plus, you'd be paying substantial money for this downgrade, and likely reduce overall reliability. Toyota has kept mechanical on the 200 and 300 while other manufacturers are putting electric fans on their quarter-ton trucks specifically because it has more capacity when needed, in spite of the NVH and fuel economy penalties.

A number of people here tow heavy through very hot conditions and while some have augmented the transmission cooling as you point out, I haven't heard of a need to improve engine cooling.

So yeah, I'd verify belt and tensioner condition, make sure the aux fan is coming on with AC, then consider putting a fan clutch on it.

Okay got it. Recently had the belt, tensioner and actual radiator replaced. So maybe I'll look into the fan clutch, see if thats bad.

Realistically, what temperature should I be worried about?

 

[04UZJ100]

The cooling system on these is designed for severe duty on the most extreme places on earth. Florida isn’t one of them.

Something is not working correctly.

 

[turbo8]

What kind of off-roading were you doing and were you in 4lo?

 

[bloc]

Realistically, what temperature should I be worried about?

Modern engines can and do run a bit hotter than older stuff we're used to, but I do start to get uncomfortable above maybe 220. I don't closely monitor digital temps but can say I've pretty much never seen my needle move off the usual spot, which correlates to about 192°F. This is in traffic up to about 110°F in Central Texas, same temps at freeway speeds across Northern Texas on my way to Colorado, over 100 in Houston where it's much more humid..

My rig has 225k and I replaced the fan clutch as PM at about 200k. Totally preventative though, I didn't notice any degraded performance, just figured it was a smart move.

 

[TeCKis300]

Agreed an electric fan is not an upgrade. All Toyota body on frame off-road vehicles use belt driven mechanical fans as it takes a significant amount of power to drive these effectively for enough airflow.

Something is going on as these rigs are very thermally stable and built for the toughest work in the middle east.

Other than having a rig in good repair... is the radiator clean and not clogged up with mud? Do you have any mods? Front bumper and under armor. These have been known to affect cooling to a degree but probably not what you're seeing. Do you have the front upper radiator cover that sits forward of the upper support and grill (important to prevent hot air from circulating). Do you have the fan shroud in place? Also does it have good seals and gaskets as it comes from the factory. All these factors play into maintaining good cooling efficiency.

I've been on big sand hills crawling, idling, and racing up in the summer. I don't see coolant temps spike to any degree and it stays under 203°F.

 

[Valgrind]

Modern engines can and do run a bit hotter than older stuff we're used to, but I do start to get uncomfortable above maybe 220. I don't closely monitor digital temps but can say I've pretty much never seen my needle move off the usual spot, which correlates to about 192°F. This is in traffic up to about 110°F in Central Texas, same temps at freeway speeds across Northern Texas on my way to Colorado, over 100 in Houston where it's much more humid..

My rig has 225k and I replaced the fan clutch as PM at about 200k. Totally preventative though, I didn't notice any degraded performance, just figured it was a smart move.

I noticed the needle move once it got above 220, anything below looked the same.
I've been running a scan gauge for actual digital temps.

Also have 227k miles, but don't think the fan clutch has ever been changed.

 

[Valgrind]

Agreed an electric fan is not an upgrade. All Toyota body on frame off-road vehicles use belt driven mechanical fans as it takes a significant amount of power to drive these effectively for enough airflow.

Something is going on as these rigs are very thermally stable and built for the toughest work in the middle east.

Other than having a rig in good repair... is the radiator clean and not clogged up with mud? Do you have any mods? Front bumper and under armor. These have been known to affect cooling to a degree but probably not what you're seeing. Do you have the front upper radiator cover that sits forward of the upper support and grill (important to prevent hot air from circulating). Do you have the fan shroud in place? Also does it have good seals and gaskets as it comes from the factory. All these factors play into maintaining good cooling efficiency.

I've been on big sand hills crawling, idling, and racing up in the summer. I don't see coolant temps spike to any degree and it stays under 203°F.

It is clean, but I have a trail tailor hidden winch mount, and my winch control box is mounted behind on the passenger side.
Also running EE skids, so I'm sure that limits a ton of airflow to the transmission. Yes, the upper cover and fan shroud are in place.

I'll grab some photos. Yeah, under 203 is what I would expect. Also, should mention that the water pump and thermostat were replaced at the same time as the belts and the radiator.

 

[Valgrind]

What kind of off-roading were you doing and were you in 4lo?

Honestly, super easy stuff, all in 4 high. Waiting for people caused a lot of idling before off-roading.

 

[Valgrind]

Other than having a rig in good repair... is the radiator clean and not clogged up with mud? Do you have any mods? Front bumper and under armor. These have been known to affect cooling to a degree but probably not what you're seeing. Do you have the front upper radiator cover that sits forward of the upper support and grill (important to prevent hot air from circulating). Do you have the fan shroud in place? Also does it have good seals and gaskets as it comes from the factory. All these factors play into maintaining good cooling efficiency.

I've been on big sand hills crawling, idling, and racing up in the summer. I don't see coolant temps spike to any degree and it stays under 203°F.

So the winch definitely blocks the bottom of the radiator; I don't think the winch box does. This is my first summer trip with the winch, but my issue is with idle/slow speed, not highway speed.
Is the fan supposed to be this far back? Seems like it's out of the shroud.
Also, is it supposed to be stiff or loose if the engine is not running?

 

[turbo8]

So the winch definitely blocks the bottom of the radiator; I don't think the winch box does. This is my first summer trip with the winch, but my issue is with idle/slow speed, not highway speed.
Is the fan supposed to be this far back? Seems like it's out of the shroud.
Also, is it supposed to be stiff or loose if the engine is not running?

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When the engine is off, you should be able to move the fan, but there will be resistance. If it spins freely the clutch is shot.

Start watching from 3 minutes. @Timmy65 lists the diagnosis procedures

 

[Valgrind]

When the engine is off, you should be able to move the fan, but there will be resistance. If it spins freely the clutch is shot.

Start watching from 3 minutes. @Timmy65 lists the diagnosis procedures

Okay, well, definitely shot then. It spins completely free.

Should I also replace the fan? I heard someone say that their fan had exploded before.

 

[bloc]

If you shut the truck off for a couple hours, does the fan roar when you start it up again and it hits that initial high idle?

Any signs of a leak from the clutch, whether from the shaft seal or the outer perimeter?

I will say how free it spins can depend on how long since the engine has run, the temp when it was shut off, a number of factors.

But if you let the rig sit for a couple hours after running and there's no resistance, you need a fan clutch.

Unless there was visible damage I wouldn't do the fan, personally. That failure seems like a fluke.. Only time I've seen that happen in seven+ years here and mine was perfect after cleaning when I did my clutch.