I'm looking to install a set of 03-05 Electric fans out of a 5.3 Silverado on to my 2001 5.3 Silverado getting ride of the pulley fan. It looks like a direct swap except for the wiring. Do they make a harness for this swap or will I just have to splice it in? Any help would be greatly appreciated!

 

Nelson Performance sells the wiring harness and a tune will be required.

 

34" radiator as well.

 

The fans only came in 2005- up 1500 trucks.

On the 05-up trucks, it's part of the headlight harness. It's Oem so it's plug and play.

Several people make the Fan harness. Some better than others.

My self, I like the PCM of NC fan harness. It's more money but it's a real nice piece. I have installed a few of them and the work really well. Certain times of the year like major holidays, they have a sale and you can get a discount on them. They will also set up the fan segments in the tune for you when you purchase the harness from them. Just ship in your PCM.

As mentioned you also need an OEM style radiator with a 34 inch core to use these fans.

 

Thanks a ton for all the responses! I now know what direction to go with and very useful information I didn't know about the swap itself! I will check out Nelson Performance here shortly.

Newb question but what is the reason to have it tuned with this fan swap?

 

Just got my question answered on the Nelson Performance website lol! Thanks again for help!

 

Im running the nelson setup and tuned with hptuners. Works perfect. I bought the correct fit fans new off ebay for around $160 I think I recall.

 

Iirc From when I did the research for the swap, the 99-02 a/c fan activates differently from 03-04. I have an 03 so I went with junkyard takeouts and had the provisions in the truck like it was suppose to have electric fans from the factory. The harness had a memory from the junkyard truck so it was a piece of cake to install. Oh ya I did have to get the bigger radiator.

 

Guarantee you that factory wiring is the way to go. I've seen both and most aftermarket harnesses use non weatherproof $3 relay sockets rated for 25 amps or less continuous service and the wires are definitely thinner gauge than stock. I haven't seen everyone's kit so I am not talking about about anyone in particular.

If you are going to pay for aftermarket just get a stock take out. If you want to go cheap just make it yourself. All it is is three relays. 2 of them are wired up with 4 pins and the other relay is wired up with all 5 pins normally open and normally closed both used. You can make this stuff on your own pretty easy. But go the extra mile and get an enclosure for the relays and fuses. Enclosures on Amazon.


As for the fans just go with direct factory replacement fans. Universal aftermarket ones aren't worth the cash and youre still stuck with making a shroud so they will be effective. I started out with universal fans and ended up not being able to use AC while idling in 90F metro area traffic. Went to direct factory replacements and 0 problems. There are two different ones for the 06 style trucks. If you look close the more expensive sets use more blades on the pass side fan.

For my conversion I used
SPECTRA CF12038 (fan set with more blades on the pass fan. others that are 40$ less have less blades)
ACDELCO PT2649 (large style connectors if you make your own harness)
Relay sockets from local parts store.
at least one 12 gauge wiring path per fan on the power side of the relay. wire from local parts store.
I am going to be adding my own enclosure soon as after about 2 years ive seen some corrosion on the contacts even with dielectric grease.
I used EFIlive to program in the information from the fans and stole some of the AC information from a 2006 Yukon.
Fan input one goes into blue 42 of the ecm and I can't remember the other one off the top of my head but if someone needs it I can look it up.

 

That's good info but most people would be intimidated wiring these from scratch. I could easily do it and still bought the premade harness.