How To: '99-'04 GMT800 OEM E-fan upgrade

[Black02Silverado]

Scott, it's been a year and you still haven't upgraded your alternator?

Nope. I did the big 3 hoping that would solve it. It helped tremendously, but my voltage still dips sometimes if both fans kick on at idle. Once I rev the engine it goes back up. That's why it hasn't been a huge priority for me.

I would thing that putting that much of a draw on that little amp alternator, that it will not last to long, probably getting super hot trying to keep up.

 

[5.3silverado]

I am wanting to do this efan swap and looking for radiator I found different thickness which one do I need and do I reuse my original radiator hoses?

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[Faxcion]

So that wiring job kicks on the fans automatically still or do you have a switch?

 

[5.3silverado]

Fan will turn on with a/c and when the pcm detects coolant temp high both fans will turn on.

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[5.3silverado]

I got electric fan unit bought $100 and I am gonna buy new radiator $155 and I found a 145 amp alternator. The last thing looking for is wire harness.

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[daddy]

So that wiring job kicks on the fans automatically still or do you have a switch?

You have to have it programmed as well. :BBP: can do that and they sell harnesses as well, if desired.

 

[ScottyBoy]

If you got the fan plugs/pigtails with your fan, then you can make your own harness using the wiring diagram I posted in the beginning of the thread. I would use 40 amp relays and 10 gauge wiring.

 

[5.3silverado]

I have access to a tech 2 scan tool can I turn on e-fan opt with that?

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[Faxcion]

Cool thanks

 

[ScottyBoy]

I have access to a tech 2 scan tool can I turn on e-fan opt with that?

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Not sure. I know you can do it if you have EFI-Live.