Blackbear tune

It's the same fans listed for both 1500 and 2500. I wonder if it was optional? Not sure about this I just know it works......and works well.

Here's one of the places I found that an electric fan is listed for a 2500HD pickup. In this case - it's for the 2010 2500HD:

http://www.gmpartscenter.net/auto-parts/2010/chevrolet/silverado-2500-hd/ltz-trim/6-0l-v8-gas-engine/cooling-system-cat/radiator-and-components-scat

The following parts are listed :

N/A 15780795 FAN MOTOR
SILVERADO, SIERRA; 6.0L; W/ENHANCED TOWING PKG.; LEFT

N/A 15780796 FAN MOTOR
SILVERADO, SIERRA; 6.0L; W/ENHANCED TOWING PKG.; RIGHT

N/A 15780789 FAN SHROUD
SILVERADO, SIERRA; 6.0L; W/ENHANCED TOWING PKG

In other places I've looked - the show an entire dual electric fan assembly in a shroud - that appears to bolt right in place of the shroud that covers the radiator for the engine driven fan.

Maybe somebody who knows GM trucks better than I do - can answer why there is an electric fan setup for "ENHANCED TOWING PACKAGE" - because if what I've read on the forums about how many CFM the engine driven fans will pull vs. the electric driven fans ........... something isn't making sense here.

This is on a GM parts site - and they're listing it.

If you go to RockAuto - drill down for a 2010 Chevrolet Silverado 2500HD -> 6.0L -> Radiator Fan Assembly .... they also have electric fans listed - and they call out with and without tow package (two different PN#'s)

So - like I said - something doesn't quite make sense here. "Tow Package" usually means MORE heavy duty and MORE cooling, not less.

Have fun !!!

Boy Racer stuff, of which is in my blood...but been there done that too often

Turtle is right and this is a RV/towing forum, so the duty cycle is way different
than pure Boy Racer duty cycle

Look up a 27 HP @ 12VDC electric motor. Note both the physical size and weight
and compare it to any of the electric radiator fan motors

To squeeze every last MPG fraction to get better CAFE numbers...some OEMs have gone
to electronic viscus coupled that is controlled by the ECU. Super expensive and
borne by us consumers. Both initial purchase and repair costs

If yours are non-electronic controlled, then traditional silicone fluid coupled
with a thermal bi-metal strip. OEMs now have wacky temp curves, etc for these
things, but the traditional viscus fan clutch had three levels. Standard/OEM,
HD and severe duty. They all freewheeled around 15% coupled to the water pump
shaft

Standard/OEM coupled at full turn on around 50%-65% of water pump shaft revs

HD coupled at full turn on around 55%-80% of water pump shaft revs

Severe duty coupled at full turn on around 75%-90% of water pump shaft revs

Above percentages are IIRC...but that is the general range.



On big brakes...there are centrifugal inertia issues that comes with the benefit
of a longer lever arm. Why the exotics and expensive stuff have composite rotors

Key is modulation, not just ability to initiate ABS in all conditions.

Testing buddies latest brake pad friction material during a volleyball tournament
weekend. About 80 mile round trip and blasted down and back on my Suburban.

Many, many blasts up to 95MPH or so and back down to about 25MPH or so. Never
initiated ABS and his stuff allowed GREAT modulation just keeping it out of
ABS...all the while pulling it down

Picture is of a tire that feathered from that single 80 mile round trip. Tire
had about 10K miles on it. Both fronts looked like this and the
rears not so much, but still feathered


MichelinLTXMS Feathered



Braking so hard...heat checked these cryo/slotted rotors on my Sub. Ditto on
the OEM, so not going to get cryo again, as that is the whole purpose of cryogenic frozen rotors. The OEM's heat checked and finally cracked clean
through...a potential interference with the pad/s friction material...


cyrorotor heatchecked


Now have NAPA HD rotors at $125/each and notice no difference from
the cryo's...PS...those cryogenic/slotted rotors also wore down and
again, why pay so much for no noticeable difference...


Why on my setup...HAVE TO HAVE THE TRAILER BRAKES LEAD my TV and
have setup my P3 so that the trailer brakes turn on before the TV's
brakes ever develop MC PSI...or get into the braking game

Hey guys, yes I plan to post real mpg numbers in the next few weeks. How I plan to do this is simple. I tested the truck on a few roads before I got the tune. I did record some mpgs at that time. After another fill up and driving some, I will replicate what I did before on those same roads. So I already have my set control numbers and soon I will have some test numbers. I will then put it together for u guys and provide an update under a new post. I already recorded in how it was done originally so this test should be very close to accurate as can be within a small margins due to weather if any. Otherwise the electric fan issue has been on my mind before. But a GM mechanic and a few Others have advised me not to do it. There are just is so many reasons for and against it. So if anybody here does it then post your test and progres with it. I for one am interested, I just replaced my clutch fan the other day...it failed when we were up in NC. Truck got warm but no over heating... We left early in the am for the ride home since we would hit the mountains when the temp outside was colder.... The new fan clutch is made for towing so it turns most of the time. But living here in Florida when everything melts due to sun and humidity, I don't mind that it's doing the job it's designed to do....

A modern Dmax fan takes about 27HP to run at WOT locked up in full cooling mode.

Good luck in finding a 15HP 12V motor to put in front of your radiator.

I'm not sure if that is the same fan or not. The ones most people are installing are the dual fan 7/9 blade configuration. Rockauto shows them if you look up an '07+ Silverado or Denali 1/2 tons, or anything of that nature. It is the heavy duty fan with towing option. I wasn't aware that GM offered an e-fan on a 2500, I honestly don't think they did but I could be wrong.

The engine driven fan DOES pull more air BUT I think that the e-fan, on a gas engine at the least, is a good option. If not, why would they put them on 1/2 tons that are "capable" of towing the same weights we can with the 3/4 tons? The 6.2L can't doesn't run much different than a 6.0L so why is it ok for them and not me? The 6.4L Hemi has e-fans.....

I had a camaro e-fan setup on my '02 Silverado and it kept it cool no matter what I was towing. The factory fans from the trucks are designed for the trucks radiator (34") so they have full coverage and baffling so they pull the air better than a retro-fitted fan from another vehicle like I did with the camaro fans. I have full confidence they will work.

Blackbear or any tuner can activate the fans and tune the temps and how they kick on. If you run in a hotter environment they can actually keep them running longer or kick in at a lower temp to keep it cool. I think the standard tuning from GM is to kick on at a certain temp or all the time on low when A/C is running and go to high as needed. They also actually turn off at speeds above 45 as the air flow at that speed is usually faster than the fans can pull it in. Unless you start running hot then it will kick on high to cool it down.

I personally wouldn't run them on a D-max or any diesel. I know people do, but I think they put off too much heat for even the best e-fan setup. AKCooper9 did this to his YukonXL 2500 already, his experience here in Texas heat was what I referred to in the earlier post.

HaulinBass02 wrote:
KW/00 will you post up some mileage numbers if you can keep your foot out of the skinny pedal? I should be able to tune my suburban today. I had been "tuned" by a guy local but I know the Blackbear tune would be better than his tune. If I pick up some MPGs then I will be ecstatic.

Also, on another note, did you know that the electric fans on the 07+ 1/2 ton trucks and SUVs fit ours as well? You would want the 7/9 blade fan configuration not the 5/7 blade from the 05 and 06 trucks. Blackbear can turn on/tune in the fans in the ECM and all you would need is a harness made by Nelson Performance. Less drag on the engine because you get rid of the clutch fan and increased cooling especially at idle or stopped.

One guy on another forum said he watched the trans temps drop while at stop lights towing his boat to the lake with his 2500 Sub! Temps never went about 205 with the fans on. Just an option you might consider. I figured if it can cool down a 6.2L Denali then it can cool me down as well!

I was wondering about the electric fan thing. Looking thru some of the GM online parts web sites I saw an electric fan listed for the 2500 Series 07 and up Silverados. It came up with a "towing option".

However - I've seen conflicting reports on whether or not the electric fan conversion is a good idea. On both the 6.0L and the Duramax 6.6L engines supposedly the engine driven fan pulls way more air than even the best electric fan.

KW/00 will you post up some mileage numbers if you can keep your foot out of the skinny pedal? I should be able to tune my suburban today. I had been "tuned" by a guy local but I know the Blackbear tune would be better than his tune. If I pick up some MPGs then I will be ecstatic.

Also, on another note, did you know that the electric fans on the 07+ 1/2 ton trucks and SUVs fit ours as well? You would want the 7/9 blade fan configuration not the 5/7 blade from the 05 and 06 trucks. Blackbear can turn on/tune in the fans in the ECM and all you would need is a harness made by Nelson Performance. Less drag on the engine because you get rid of the clutch fan and increased cooling especially at idle or stopped.

One guy on another forum said he watched the trans temps drop while at stop lights towing his boat to the lake with his 2500 Sub! Temps never went about 205 with the fans on. Just an option you might consider. I figured if it can cool down a 6.2L Denali then it can cool me down as well!

I can completely understand that. By all means, I'm not trying to steer you away from the larger brakes, I was trying to offer an alternative but since you have pretty much been there with a different vehicle than you know what you need better than I!
NorCal is "probably" going to steer you towards what I did with mine, especially if you are going to end up leveling it at any point. I'll spare all that here, I'll send you a PM with what all I did and why. It's pretty much what ANY of them recommend for a leveled GM IFS vehicle due to their factory limitations.

NorCal truck has a DIY on how to add some space in the front wheel wells if it's needed:

http://norcaltruck.com/2007-5-2013-chevy-gm-large-fender-mod

Yes - it could be the extra width that rubs. The difference in width between a 265 and a 285 tire is about 3/4 of an inch. Combine that with slightly increased diameter of the 20" tire and it may come **** close to rubbing with the wheels cranked for a turn.

Part of my obsession with the brakes is that I have spent most of my life driving sporty type cars. I like things that go - but I like them to stop too. Given that the truck will be used for hauling and/or towing substantial weight - and out here in NE there are mountains that do have some steep roads going thru them - I'm concerned that brakes that I consider to currently marginal at best - would be outright dangerous if I was in a mountain road situation. I can see the darn truck just not stopping at all.