Most direct bolt on Cooling fans for GMT400?

[ryeguy2006a]

It depends on what computer you are running. From what I understand the Black Box ECU only has one output for a fan, so many people will hook one fan to the fan output and the other fan to a trigger from the A/C in the truck. If you have done the 0411 ECU Swap or an LS swap like my truck, you can program the ECU to have two fan outputs (ground) and hook them into a relay to trigger the on/off functions. I can take some pictures and do a little write-up if anyone is interested.

 

[c1500deathtrap]

lincoln mark 8 fan fit pretty well for me.

 

[JackE]

Does the Black Box ECU already triggering that pin, or does it need to be turned on through a tune? I'm not doing anything to warrant a 411 ECU, but I will be sending my ECU to BBP for a few changes.

 

[df2x4]

Does the Black Box ECU already triggering that pin, or does it need to be turned on through a tune? I'm not doing anything to warrant a 411 ECU, but I will be sending my ECU to BBP for a few changes.

Needs to be activated in the tune I believe, @Cokeman95 can clarify I'm sure.

 

[Cokeman95]

Does the Black Box ECU already triggering that pin, or does it need to be turned on through a tune? I'm not doing anything to warrant a 411 ECU, but I will be sending my ECU to BBP for a few changes.

The auxiliary fan setting has to be enabled in the black box.

Sent from my SM-G965U using Tapatalk

 

[Cokeman95]

I’d love to hear more about this setup. How it’s wired, etc.

Here's a brief rundown

https://www.gmt400.com/index.php?posts/1007294


They're 05+ truck fans with a cover I made out of steel from Lowe's. Nothing terribly fancy but does the job. Any more questions feel free to ask.

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[JackE]

Any questions feel free to ask. I'll do my best to answer them.

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My '99 already has a factory pusher fan in front of the radiator. Is that running from the one wire from my computer? It only seems to kick on occasionally when the A/C is running. I haven't been able to pinpoint what it's trigger is. My plan is to install the dual electric, run one off the computer trigger wire, and the second off the A/C signal wire.

 

[Cokeman95]

I'm not sure how that pusher fan is wired. The pin for the auxiliary fan is pin 9 in the connector marked black going to the black box. I'd check to see if that has a pin in it.

Mine are run off the one pin for low speed and high speed is triggered by the a/c.

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[454cid]

My '99 already has a factory pusher fan in front of the radiator. Is that running from the one wire from my computer? It only seems to kick on occasionally when the A/C is running. I haven't been able to pinpoint what it's trigger is. My plan is to install the dual electric, run one off the computer trigger wire, and the second off the A/C signal wire.

I believe it's when the coolant temp reaches 225, or the AC head pressure reaches some limit.

 

[Supercharged111]

I believe it's when the coolant temp reaches 225, or the AC head pressure reaches some limit.

Either/both. All PCMs supply a ground for a relay coil. Or 2 if you run the fans in a low/hi setup.