Towing upgrade

Ok, comments please, have a 04 dbl cab 4x4 sr5 TRD....planning to do timing belt replacement drill....while apart, am considering improving tow capabilities with heavy duty fan clutch install as well.....
Anybody here plainly explain how the heavy duty fan clutch will operate differently than the standard fan clutch?
Yes, probably will install Trans cooler as well....with the Trans cooler in front of the radiator, will this effect the cooling of radiator fluid negatively?
Will replacing stock thermostat with TRD thermostat (used specifically with supercharger) improve cooling capabilities, too?

 

A fan doesn't spin at the same speed as the engine, the clutch allows it to slip even when engaged. A heavy duty lets it slip less than the standard one.

 

Better yet ditch the clutch fan and go electric. Free up some power and mpg

 

That HD one seems like its always roaring!! Making lots of noise, just like it does on start up with a regular fan, but it stays on for much longer! I bought one a while back when i did a radiator swap, figured itd be good to have. I hated it so much i put the old one back on. I swore it robbed a bunch of power too with it always spinning so much...

The one i bought wasn't an aisin though....

 

Trans cooler won't affect radiator cooling at all, but it will help trans temps a TON. I did mine this summer, and I noticed a drop of at least 20 degrees going down a freeway. The temps drop so fast when not under load. I have yet to tow anything but man I know it will help when I do. I got this http://www.bmracing.com/products/70...13000-btu-rating-black/?mk=&yr=&md=&smd=&eng=

The large one is 1 1/2" thick as opposed to 3/4" and won't fit (well I wouldn't want to try after installing mine) I had to buy a little more hose however. Make sure you get the right length as it is pretty pricey, and to come up short would suck. I wouldn't worry about a clutch, but that's just me. This is plenty of cooling capacity.

 

look into the brake upgrade. I think you can use the 06 prerunner caliper, rotor, and pads on our trucks. just need to make sure the caliper will mount AND not rub on the inside of the rim.

 

He has an 04. It would be a tundra brake upgrade

 

The calipers used on 2nd gen prerunners were the same ones used for the tundra recall fro 00-03. Ive already verified it. They should work as well. when i get to work, ill see if i cant pull a caliper off of each to compare some critical dimensions.

 

The threads I've seen you want the 13wl calipers off the tundras

 

2nd to the cooling issues is the piss poor oem braking system so do the tundra brake upgrade so you can stop it as needed

 

Yes you use electricity, but that doesn't rob you of horsepower. Deleting the clutch and going electric also increases your mpg by 1-2mpg

 

It is hard for me to believe that an electric fan can increase your MPG by 1-2. Why wouldn't Toyota do this modification to begin with if this was true?

 

If you have 4 x 4, you already have the heavy duty fan.

 

I wonder this too, why not electric water pumps and oil pumps.

Reliability and cost is my guess. I'll bet on an off road vehicle anything electric is a liability due to possibly being submerged. A good mechanical unit that's sealed and powered by a belt seems the way to go. Still easy fixes too. Cost of a water pump is like 50 bucks.

The load on an engine from an alternator is constant, as it rides on a shaft with bearings. Voltage is regulated electronically. Demand for power doesn't create more load by offering more "resistance" internally. Switch alternators to a higher output, and maybe you'll see a small but constant change due to heavier internals? I dunno, but the load is still constant for the engine.

 

Alternator load is not constant. When it's off it free-wheels. When it's charging it takes power to turn. The heavier the magnetic field the more force it takes to turn. The higher the electrical load the more often the alt will be charging so the greater the loss to the electrical system. The voltage regulator doesn't directly control output, it controls the magnetic field in the alt to increase or decrease the alts output. When it sees a fully charged battery the alt will have no output. The greater the deficiency it sees the great the field will be, the greater the output until its maxed. And the greater the field, the more energy it takes to turn.

A regular 55a alt takes about 1-2hp, that will increase with output. A properly working clutch fan takes 3-5hp.

The amount of energy it takes to move a set amount of air doesn't change depending on the force used to turn the fan. If you want to move x in y time it will take z energy.

The advantage the electric fan will have over a mechanical is that it will be off entirely when the vehicle is moving fast enough to keep it cool, and only turn on when slow or at a stop. If you're on the highway all the time the fan will be off most of the time and you'll see savings. If you're stop and go all the time, fan will kick on all the time, no savings.

A clutch fan will require decreased energy to turn when cool and the clutch engages more force when it's hot. Which is why you don't see too many non-clutch fans on anything newer than the 70's. But there will always be a minor parasitic drag even when it's as close to free wheeling as it can get. However the actual energy used difference is pretty negligible.

 

FYI, doing all those things doesn't increase the amount the truck can tow, just remember that. Those upgrades only make it easier on the transmission and engine, but pushing the specified tow ratings is both unsafe and illegal. They are rated to tow 5500#, I personally wouldn't even come close to towing that much with mine, maybe 3500# max but that's just me. Then again, I'm used to towing with 3/4 and 1 ton diesels all the way up to class 8 OTR trucks.

Another thing I'd highly recommend upgrading on your Tacoma is bigger brakes and a brake controller will make stopping much less of a white-knuckle, sphincter tightening experience. Many guys on this forum do the Tundra brake upgrade and swear by it and it's pretty straightforward to do. The size difference between the two rotors is substantial and makes a huge difference in stopping ability.

 

Exactly. The fluid in the clutch gets more viscous with heat, so at a stop or slow it tightens up and turn more to keep the engine cool. When there's more air moving through the system the air cools the clutch and it becomes less viscous and gets closer to free-wheeling so it's not pulling unneeded power from the engine. A fan on the interstate isn't going to pull more air through the radiator than the car moving will force through, so there's no need for it to be 'on'.

 

Agreed load capacity doesn't increase. The wear and tear on your vehicle is reduced a bit by additional cooling capacity. Always a plus. But I wouldn't replace a ton of stuff for a few extra HP however. Not too cost effective for the gains.

Indy, I'm simply curious not trying to be disagreeable. You are right about the force to turn said magnet, but your science regarding electromagnetism, power generation and regulation is wrong.

If you have the rotor and stater constantly turning that by nature (laws of electromagnetism) current will be generated. It makes sense that the greater the magnetic force, the greater the energy required to turn it. But by design, a standard Alt vs High output, (larger magnets or whatever) the magnetic force doesn't change, just the output, and at different rpms as well. Read the article below, some alts produce more power at low rpm by design.

If the rotor is spinning in the stater, current is generated, and that can't be stopped unless you stop the rotor.

Voltage is diverted and controlled by diodes and regulators. Regulators don't control magnetic fields, they regulate current already generated. Not the field that generates current. It's an "always on" accessory, I'm pretty sure about that.

If I am wrong, I would be happy to have been corrected. If I missed anything please let me know.

A little clarification.

http://auto.howstuffworks.com/alternator.htm

 

Because the fan spins constantly, the clutch juts controls when it engages to spin faster. So it's constantly robbing you of some hp, and then when it engages r robs you of even more. Electronics fans don't spin until they get the signal the coolant is too hot, then they cool it down and shut off.

The electronic draw from the increased load on the alternator is negligible compared to the fan which physically takes effort to spin.

 

Because we're talking about a 2004. His engine is the same technology as when the 3.4 first came out in 95.5 minus his has fly-by-wire throttle control. I'm not sure about 2nd and 3rd gens, if they use electric fans, but I don't know if any new car that still uses clutch fans.

Plenty of threads on here of the increase in mpg increase you get by deleting the parasitic hp draw from the clutch fan.