Miklo's 2001 Silverado 2500HD Build Thread

Mikloangelo

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I have a pair of electric fans, that I just took off of a 2018 Suburban, simply because I was putting a radiator in it and the owner wanted all new. The Suburban is a 2018 with a 5.3 and 97k miles on it. Comes complete with the shroud. All is intact and work perfectly. Only thing needed is 6 of the 5mm-0.8 thread mounting screws. I had to use the old screws to mount the new fans to the new shroud.

I would sell to a member here for $80 plus the shipping. All of it is in perfect shape. No broken pieces on the fan shroud or fans, motors and blades. There is even one marked left and the other fan right.

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Where do you pick up the power to turn them on? This takes place of the OE fan?
 

ORVietVet

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Honestly haven't thought about. I did read about people doing that. Just not sure how effective they are for a 6.0L doing some occasional towing. This is supposed to take place of the fan?
Yes, the electric fans are very efficient. I had a 2002 Tahoe with the tried and true fan clutch. I now have a 2005 Tahoe and it has the electric fans. quieter, more efficient and better fuel mileage. BUT, with either set up, you better have a good flowing radiator or you are gonna fight it.
 

ORVietVet

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The power is supplied by of course a power supply thru relays and thermostat set ups that turn them on when temp reaches a certain point and if a/c is turned on.

I would only assume that it can be controlled through the PCM and correct harnesses. there is likely a thread or two available at another forum I belong to at Tahoe/Yukon Forum. I know there are guys that do it there. You could also just hard wire them to switches and turn them on when you want. I know that a cooling system in good working order, does not need a fan when traveling at highway speed. Unless you are towing.
 

ORVietVet

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If you want to do the research, here is the OE Genuine GM part numbers: Left fan is 85565556, right fan is 85565557 and shroud is 23123635. Came off of a 2018 Suburban with a 5.3 engine. This set up fits 2015 thru 2020 Suburbans with 5.3 or 6.2 engines. Also the 1500 Silverados with the 5.3 and 6.2 engines.
 

AuroraGirl

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To give you folk some insight about how my brain works here's a run down if my thought process.

I got to replace the heater core, which involves removing the dash. So I might as replace all the blend door actuators and Will probably repaint the dash and trim with some SEM paint while I'm at it.
If I replace my heater core, I should go ahead and fix the AC. I don't know if it has a leak or if the compressor is bad, so I bought a vacuum pump and and entire new AC system.
Also if I'm replacing the heater core, I should address my coolant leak. Ordered new radiator, new hoses, new water pump.
If im replacing the radiator, i should go ahead and replace the radiator core support, since it has previous damage from a wreck, which caused my fan to wear into the fan shroud. So I ordered new fan shrouds, fan and fan clutch.
If im taking off the radiator core support, i should buy new headlights assy, and blinker light assy, sealight LEDs, and headlamp mounting brackets since they were also messed up due to a previous wreck.
If I'm taking off the water pump, I will have access to the timing chain and sprockets, the cam, oil pump, cam retainer plate, serpentine belt system with new tensioner and idler pulley. So i ordered Michigan Motorsports chain and sprockets, Texas Speed and performance Stage two cam, and Melling 10296 oil pump.
If I'm taking off the water pump, I should serpentine belt system with new tensioner and idler pulley and new steering pump, since its leaking.
If I am changing the cam, I should swap my heads to 799 heads and use Fel-Pro gaskets. New drivetrain components from BTR and Michigan motor sports.
Since im swapping heads I should change out the lifter. Ordered BTR LS7 lifters and trays, Along with new ARP bolts for the heads and headers, and gaskets for the headers and intake valve manifold.
If im taking the intake manifold out, i should delete the EGR valve and EVAP purge solenoid.
If im giving this pig some extra horsepower, and getting a tune, i should get new headers and exhaust. I have yet to buy these, but the time is coming.
Since I have the front clip ripped apart, i should replace the front bumper and grille. Which were also damaged in the wreck. Havent bought yet, but will when things start going back together.

I have never done any top-end work before on any vehicle, or any engine internals for that matter, but I'm confident i can do this. YouTube is incredibly helpful and beats trying to decipher a Haynes manual.

I hope everyone enjoyed reading that. This is how my mind works sometimes. Its a high-mileage truck, 284,000 miles, and many things just need to be replaced. But the performance stuff is more for smiles. My wife has been going crazy watching several boxes a day show up for the last two weeks.
DO NOT delete the EVAP purge solenoid. also upgrade your driver side valve cover for the better pcv

Pump most likely is leaking from the reservoir, replace the seal or reservoir. keep the pump.
 

99Sierra2500

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The power is supplied by of course a power supply thru relays and thermostat set ups that turn them on when temp reaches a certain point and if a/c is turned on.

I would only assume that it can be controlled through the PCM and correct harnesses. there is likely a thread or two available at another forum I belong to at Tahoe/Yukon Forum. I know there are guys that do it there. You could also just hard wire them to switches and turn them on when you want. I know that a cooling system in good working order, does not need a fan when traveling at highway speed. Unless you are towing.
Some of these trucks also had a cooling limp mode, shut down cylinders.
 

99Sierra2500

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debuted on the northstar, quickly went to the 3800, then presumably also things like the small block v8 with caddy/corvette/F bodies, id assume first
I remember reading about it in Road and Track or whatever, back then the subscriptions were cheap, and good to throw into the waiting room at the shop. I have heard people say they have limped trucks home, don't know how they did.
 

Mikloangelo

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I have a pair of electric fans, that I just took off of a 2018 Suburban, simply because I was putting a radiator in it and the owner wanted all new. The Suburban is a 2018 with a 5.3 and 97k miles on it. Comes complete with the shroud. All is intact and work perfectly. Only thing needed is 6 of the 5mm-0.8 thread mounting screws. I had to use the old screws to mount the new fans to the new shroud.

I would sell to a member here for $80 plus the shipping. All of it is in perfect shape. No broken pieces on the fan shroud or fans, motors and blades. There is even one marked left and the other fan right.

View attachment 5088View attachment 5089View attachment 5090View attachment 5091View attachment 5092View attachment 5093View attachment 5094View attachment 5095View attachment 5096View attachment 5097
Where do you pick up the power to turn them on? This takes place of the OE fan?
The power is supplied by of course a power supply thru relays and thermostat set ups that turn them on when temp reaches a certain point and if a/c is turned on.

I would only assume that it can be controlled through the PCM and correct harnesses. there is likely a thread or two available at another forum I belong to at Tahoe/Yukon Forum. I know there are guys that do it there. You could also just hard wire them to switches and turn them on when you want. I know that a cooling system in good working order, does not need a fan when traveling at highway speed. Unless you are towing.
I will have to look into this a bit further. I know its been done many times over. Id rather it turn on itself, so one less thing for me to remember. I appreciate the info and the offer to sell the e-fans. If i decide to go that route i will reach out
 

Mikloangelo

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Well i had a few hours to kill before some friends came over for a crab boil, so i decided last night i would just remove the hood and fenders to make thing simpler if a problem comes up. I was worried about a broken header bolt and having to drill it out. From there I moved all the wiring and throttle cables out of the way, unplugged the coils and fuel lines. Removed the intake manifold, and slowly worked on removing the headers. I have been PB blasting all the hardware since yesterday and everything came right out, luckily. Next week I will remove the heads and pick up the 799 heads.
 

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Mikloangelo

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The only hang up ive had so far is removing the dang AC compressor. I can remove 3 out of the 4 bolts. The last bolt is directly behind the engine mounting bolt. I didnt mess with it too long, since i had friends coming over soon. I will have to look at it some more and deal with it next week as well.
 

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ORVietVet

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A local person asked for some measurements. The core coverage part of the shroud is 35" wide and 18" tall. The total width is 38" including mounting and 19" tall. The depth is 5.5".
 

AuroraGirl

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I remember reading about it in Road and Track or whatever, back then the subscriptions were cheap, and good to throw into the waiting room at the shop. I have heard people say they have limped trucks home, don't know how they did.
A North Star with proper functioning limp home can operate without coolant at 55mph for an hour
 

Marky Dissod

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Yes the pair of electric fans takes the place of the mechanical clutch fan. They are powered by an electrical fan harness.
Hopefully you're not thinking 'this is some krabpy aftermarket horseschidt' -
think of it as updating your radiator cooling package to 2005 / 2006 GM OE.
It's worth 5-10 horsepower (depending on RpM) and a 2-3MpG depending on how you drive, so it will eventually pay for itself.
 

AuroraGirl

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Yes the pair of electric fans takes the place of the mechanical clutch fan. They are powered by an electrical fan harness.
Hopefully you're not thinking 'this is some krabpy aftermarket horseschidt' -
think of it as updating your radiator cooling package to 2005 / 2006 GM OE.
It's worth 5-10 horsepower (depending on RpM) and a 2-3MpG depending on how you drive, so it will eventually pay for itself.
I’m pretty sure the 2006 2500hd still kept a mechanical fan just like my 2005 2500hd, so can it keep up the demand of the air flow for trailering?(oil cooler on both tanks, auxiliary oil cooler for transmission, and hydroboost cooler on the side, and air conditioning)
 

Marky Dissod

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pretty sure the 2006 2500hd still kept a mechanical fan just like my 2005 2500hd, so can it keep up the demand of the air flow for trailering?
(oil cooler on both tanks, auxiliary oil cooler for transmission, and hydroboost cooler on the side, and air conditioning)
Not sure about the GMT800 '05-'06 fans, but
there are GMT900 electrical fan motors that work well as upgrades in conjunction with a GMT900-KW1 alternator.
 

Mikloangelo

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Yes the pair of electric fans takes the place of the mechanical clutch fan. They are powered by an electrical fan harness.
Hopefully you're not thinking 'this is some krabpy aftermarket horseschidt' -
think of it as updating your radiator cooling package to 2005 / 2006 GM OE.
It's worth 5-10 horsepower (depending on RpM) and a 2-3MpG depending on how you drive, so it will eventually pay for itself.
No I know the juice would be worth the squeeze. My hold up is I have all new parts for the mechanical fan including new shrouds.
I don't mind the mechanical fan. Yeah some added HP and more bay clearance, but I don't mind. Not like I can't change my mind later. Seems an easy enough install.
 

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