2003 Suburban EASIEST EFAN Swap Ever!!

[Rocket Man]

Will the NNBS fans from 07-14 bolt up the same as the 05-06 factory fans? Would you happen to know if the plugs are the same for NBS 05-06 fans and 07+ NNBS fans? Asking all this because I just found a clean set of NNBS fans in a pick your part and considering bringing them home and going about the conversion.

Is the factory relay block, fan controller the same between 05/06 and 07 and later? I already have the fan controller/relay block from a 2005 Tahoe, but had not picked up the fans & shroud yet.

I seem to remember that the 07+ E-fans were superior to the earlier 05/06 for some reason I can't recall????
Thanks all.

I just looked at my 08 Silverado fan setup. The plugs on the fans look the same. The relays, controller etc are not the same at all though. The relays are integrated into the main under hood fuse block.

 

[mattt]

Thanks for the replies. I went down the you tube rabbit hole last night researching this conversion. The fans I found are from an 07 Avalanche. I looked back at the pictures I have of it and it is the common 7 & 5 blade fan setup. So I had first thought it was any 07 and newer vehicle but from what was found last night, it appears it's the 09 and later vehicles with the improved 9 & 7 blade fans. Can someone in the know confirm that break point?

Also found the info that Rocket Man just posted about the stand alone, add-on controller, relay setup from the 05-06 is what you want, since in the GMT900's from 07 and forward, they integrated the fan control relays into the main power distribution box.

I've never had any overheating issues on my 04 Tahoe with 335k miles under the belt and it's original mechanical fan & clutch. The worst I've had is poor A/C performance on hot days here is Socal or when I'm in the desert, at the river. So I was considering just keeping the factory mechanical fan setup. However the more I've read on this conversion, it's brought me over to doing the swap. Anyone playing devil's advocate for keeping the mechanical fan?

 

[mattbta]

I'm in Texas and the stoplight A/C performance is crap with my 04 clutch fan, even with a brand new clutch. Just do it!

I just got two sets of 5/7 fans. OCD me wants the newer, better ones...but I figure that's an easy swap once I do the conversion. I have the harness. Now all I lack is the tuning and two 13mm bolts. I thought I grabbed the right size, but they were the 10mm from a fan shroud.

Anyone know the radiator bolt part #? For whatever reason, my searching is crap. EDIT: 11516931

 

[Rocket Man]

Thanks for the replies. I went down the you tube rabbit hole last night researching this conversion. The fans I found are from an 07 Avalanche. I looked back at the pictures I have of it and it is the common 7 & 5 blade fan setup. So I had first thought it was any 07 and newer vehicle but from what was found last night, it appears it's the 09 and later vehicles with the improved 9 & 7 blade fans. Can someone in the know confirm that break point?

Also found the info that Rocket Man just posted about the stand alone, add-on controller, relay setup from the 05-06 is what you want, since in the GMT900's from 07 and forward, they integrated the fan control relays into the main power distribution box.

I've never had any overheating issues on my 04 Tahoe with 335k miles under the belt and it's original mechanical fan & clutch. The worst I've had is poor A/C performance on hot days here is Socal or when I'm in the desert, at the river. So I was considering just keeping the factory mechanical fan setup. However the more I've read on this conversion, it's brought me over to doing the swap. Anyone playing devil's advocate for keeping the mechanical fan?

There’s zero reason to keep it imo other than it does cost a bit to do the swap.

 

[mattbta]

11516931

This is the PN for the radiator bolts/fan bolts. For the time being, I was too lazy to go hunt at the yard I went to yesterday so I paid a premium at the Stealership. (Probably woulda paid less at the Chevy dealer I went to first, but they didn't have any - Caddy dealer down the road from them had em.)

 

[mattt]

Which fans are better to use on a conversion, the 5/7 blade fans & shroud or the later 7/9 blade fans and shroud?

Has anyone run across a thread that details why GM changed the fans from 5/7 blades to 7/9? I've been looking around and can't find the info I thought I'd seen long ago.

Which one moves more air? Which is quieter? Which is more resilient, long lasting? Let's hear your experiences with the E-fan swap. Thanks!

 

[mattt]

Quick question that's not addressed in any of the threads or videos I've seen for E-fan conversion. My 04 has two harness connectors with a bunch of wires attached in place where the 05-06 E-fan relay block is supposed to sit and clip in place. The relay block won't clip down or sit correctly with these wires and connectors there. What is the correct way to re-route or re-attach these 2 harness connectors that are factory on an 04 Tahoe? Yeah, I could just remove their attaching clips and let them dangle, but that would be less than ideal. If no one else has noticed this before, I'll take a trip to the PYP to see how the factory ran all these components in an 05-06.

 

[mattt]

I figured out what the unknown wiring is. At first I thought it was for Flex Fuel stuff because I was only seeing it on "Z" engined vehicles at the yard yesterday, but then I saw it on a "T" engined vehicle so that idea was out. The 2 plugs occupying that space are for the Autotrac transfer case. Once I figured it out, then it made sense....4wd has the 2 plugs there, 2wd is wide open in that space. There were two 05-06 Tahoe/Suburbans at the yard I went to yesterday but neither had those plugs so I first thought it was an earlier model thing, but nope those two were both 2wd rigs. What I haven't seen in the flesh yet is a 4wd 05-06 rig to see how the factory configured all this to work in the same space. I'll be going later today to a yard that has 2 rigs with this config(05-06 4wd) so I'll see what the factory did.

 

[mattbta]

I figured out what the unknown wiring is. At first I thought it was for Flex Fuel stuff because I was only seeing it on "Z" engined vehicles at the yard yesterday, but then I saw it on a "T" engined vehicle so that idea was out. The 2 plugs occupying that space are for the Autotrac transfer case. Once I figured it out, then it made sense....4wd has the 2 plugs there, 2wd is wide open in that space. There were two 05-06 Tahoe/Suburbans at the yard I went to yesterday but neither had those plugs so I first thought it was an earlier model thing, but nope those two were both 2wd rigs. What I haven't seen in the flesh yet is a 4wd 05-06 rig to see how the factory configured all this to work in the same space. I'll be going later today to a yard that has 2 rigs with this config(05-06 4wd) so I'll see what the factory did.

View attachment 373930

Thanks for clarifying. I haven't installed mine, yet, but it's RWD so this makes sense.

 

[Rocket Man]

I figured out what the unknown wiring is. At first I thought it was for Flex Fuel stuff because I was only seeing it on "Z" engined vehicles at the yard yesterday, but then I saw it on a "T" engined vehicle so that idea was out. The 2 plugs occupying that space are for the Autotrac transfer case. Once I figured it out, then it made sense....4wd has the 2 plugs there, 2wd is wide open in that space. There were two 05-06 Tahoe/Suburbans at the yard I went to yesterday but neither had those plugs so I first thought it was an earlier model thing, but nope those two were both 2wd rigs. What I haven't seen in the flesh yet is a 4wd 05-06 rig to see how the factory configured all this to work in the same space. I'll be going later today to a yard that has 2 rigs with this config(05-06 4wd) so I'll see what the factory did.

View attachment 373930

Please follow up here when you figure it out, I’m curious. There must be a way.