Fans for Transmission cooler

[traveler]

Hey I have what I hope is a simple question.. I just bought two 7" fans to mount on the auxilliary transmission cooler. I know how to mount them, but not sure how to wire them. Should they be wired separately? in series? in parallel? I don't want to mess with thermostats, just a simple switch, or wire it to come on with the ignition.

 

[Turdle]

Well, you do want a relay. It should be ok to use just one for less than 20amps.
The relay will keep the current load out of the cabin and under the hood.

 

[Turdle]

What the diagram doesn't show, is the fan is also grounded . The fan positive lead is marked. change direction of fan flow by reversing the blade, not the wires.

 

[traveler]

So its basically just like wiring my Driving lights.... except obviously I'm powering a motor not a light. And it'd be ok to run them in series, so long as I use heavy enough wire?

Not sure I know what you mean by reversing the blade... But I'll look into them when I dig further into the box. I ordered these specifically because they moved more air, and they could be either push or pull fans.

 

[shucker1]

@traveler ,

You want a parallel circuit.

Tie the (2) positive fan leads together and then tie both of those to your power source.
Both negatives go back to body ground or negative battery terminal somehow. (Battery negative is best.)

A series circuit would be tying one fan lead positive to the other fan lead negative.

Like @Turdle said, make sure to use a relay so you don't have a "Road Side Winnie Roast" with your rig.

 

[traveler]

Ahh... That does make a lot more sense, thanks. And yes was planning on a relay. Just hope I can find all my electrical parts. I have an extra relay, and the right gauge wire, but having just moved I don't know where it is!

 

[traveler]

Ok... I have hit a snag. Where can I find a source of switched power under the hood? I want the fans to shut off with the ignition.

 

[Turdle]

I'd have to look, but honestly you'll remember they are on when you turn off the truck.

 

[Turdle]

How about using a switched power for your switch instead?

 

[traveler]

LoL yea I've been thinking that same thing. I'm just being lazy.

 

[traveler]

How about using a switched power for your switch instead?

I.E. find a switched power source inside the truck?

 

[shucker1]

Tap into the 12 VDC positive lead for the fuel pump supply to drive the relay coil for your fans?

Use the downstream side of the fuel pump relay.

I.E. When the fuel pump is told to come on your fans come on. As long as the fuel pump is running your fan relay stays closed and your fans run.

 

[08EddieCA]

Fastronix 6 Circuit LED Fuse Block and Cover Kit with ATO/ATC Fuses - on Amazon
Not sure if this will help your situation. I have a fan running over a trans cooler. This fuse add-on may help. Note I'm not very proficient with wiring etc.

attached fan and thermostat to upgraded trans cooler

• 08EddieCA
• May 19, 2017

Pusher fan behind front bumper cover. Hayden cooler.
Still runs great as of June 2018

 

[traveler]

Well they are in and running. They are controlled with a switch and a relay. Couldn't get them to go off with the ignition. But I haven't given up, just wanted to get them running in time for an upcoming trip.
They were advertised as 7" fans but they are more like 8.5". They are wider than the cooler but they will work.
I'll get pics later. I'm already showered and cleaned after crawling in and under the 110 degree truck, don't wanna crawl under it again right now!

 

[Mbrooks420]

What about the 4wd pigtail plugged into the radio bezel?

 

[traveler]

What about the 4wd pigtail plugged into the radio bezel?

Well if its there, that might work. My truck came equipped with AWD, but the pigtail may still be there. I'll look into it if I've got time this week. Thanks.

 

[Mbrooks420]

The pigtail will be where the 4wd switch would be on a v6. Just not sure if it's powered. I think it is.

 

[traveler]

Ohh I've been in there before. I got a V6 faceplate and mounted my driving light switch where the 4WD switch would have been. Can't remember if I saw a pigtail not. Probably did.

 

[CDW6212R]

That 4WD wiring is in the dash harness on all models. I don't know if any wiring is out under the hood for it though, it's different wiring forward of the firewall.

You could use the oil pressure switch wiring to trigger a relay. I used that to trigger the headlights of my mail truck. Just be careful tapping onto it, don't hurt that wiring.

 

[Mbrooks420]

You can use a constant 12v source for the power feed to the fans, and a switched power source for just the relay coil (trigger) as mentioned above. No need for both to be switched, or even come from the same source.