My LS1 fans with Nelson harness are working great!

I'm thinking it'd be great to have a switch to control from auto / low / high on both fans. How difficult would this be? Also what about a series of led's to indicate fan staus.

 

It would be easy....just need a switch, some extra relays, and some diodes.

If you got the light-up switches you wouldn't need LED's.

You would just need a switch that would tap into the PCM ground wire to ground it manually, that would make the fans come on low.

If you wired it up so that it grounded the PCM wire and put 12V on the a/c trigger wire (this is where you need the diode - if you put 12V on that wire without one you will cause the a/c compressor to engage), using a diode, a few relays, and maybe a 3-position switch, off will leave the fans operating as they do now, position 1 would just ground the PCM wire, and position 2 would ground the PCM wire and put 12V on the a/c trigger wire. That's basically how mine worked, except I only did off and high.

 

Any updates on this thunder550???

 

The problem is not fixed, but is substantially better. Last week with the e-fans I had to baby it up the hill with the heat on and I still saw 248*. Yesterday with the clutch fan I was on it pretty hard with the a/c on and I saw a high of 227*. I just remembered that my water pump has a lifetime warranty on it, I may take the truck in and tell them I am having overheating problems and get the pump replaced under warranty. Then all I have left to check is the radiator.

BTW, for anyone who is interested, the fan shroud from an 03 Silverado SS fits the 34" radiator in a 1/2 ton perfectly, but an 03 2500 HD shroud will not - I think the engine sits deeper relative to the radiator in the HD's because the fan was rubbing the top of the shroud when I tried it.

 

It's probably becauset he HD uses different motor mounts.

 

Psh. Where were you when I was buying the wrong part? Thanks

 

Well that is some what good news for the rest of us with 05 fans wondering if we should install them. Now hopfully you can figure out what the hell is your trucks problem.......
Good to know about the fan shroud I think the 04 SSS is the same as a 03 too, now that we know the HD's wont work.

 

OMG I just thought of something!!! Look on your efan housing...on the outside where the fan housing has two tabs. One on the driver side and one on the pass. side. Those tabs should fit in between the hooks on the radiator!!! NOW....on my e fan setup (F-A-L) I can adjust those tabs so the fan housing fits absolutely snug against the radiator!!! Also the same is true for if I want them to not fit in quite as tight!!! I can adjust those tabs on the sides so that when the efans are inserted in the hooks on radiator, it pushes them extremely tight against the radiator!???

Reason I thought of this is because with both of my efans cranking (when I first got them) I could not get my truck to stay cool. When I pulled them back out and adjusted those side tabs so that the fan housing was basically being forced against the radiator as hard as it could be, my temps never, and i mean never see above 200!! Towing 2700 lb car across the rolling hills of virginia in 90*+ with A/C on!!!!!
Check to see if those tabs are adjustable, if they are not then this is probably the problem!!! If you can adjust them, pull the tabs as close towards the front of the fan housing as possible to make them fit really snug against the radiator when inserted into the hooks.

 

holy crap that is simple! Hate to see that's what the prob was, but at the same time I hope for thunder that's it! LOL

 

Oh and to touch on the subject of too many amps being drawn from the fans... I just bought a capitor like the ones used in car stereo systems. Works great for me and I have a 200amp alternator!!!