Ac isn’t cold at idle

[BNielsen]

My truck doesn't have any issues with heat when towing, and the fans are set to turn off above 35mph. Were the truck to get hot and need a fan while moving, engine driven is superior. I will not remove the engine driven fan from my dually, but I haul big and heavy with it. What radiator are you looking at for an upgrade? Stock 3500 or aftermarket?



Depending on what you're working on, the size isn't always an issue. The air doesn't cool the engine though, that's what the coolant is for. The dually will throw some serious heat though after a mundane drive. I'm amazed the stock cooling system works so well on it.

Aftermarket 3" thick rad, and probably running a good coolant like Shell/Rotella and maybe Water Wetter, similar set up to what someone is running on his truck. (That someone is in a groupchat with me, Biggershaft96, Gavin, and a couple others)
I can't seem to find a straight answer on which is better, I do plan on towing with my truck, but I'll probably only ever gross 13K max combined and that'll probably be a rarity.
I know after my quick 6 minute drive home my engine bay is like the surface of the sun.

 

[Supercharged111]

Aftermarket 3" thick rad, and probably running a good coolant like Shell/Rotella and maybe Water Wetter, similar set up to what someone is running on his truck. (That someone is in a groupchat with me, Biggershaft96, Gavin, and a couple others)
I can't seem to find a straight answer on which is better, I do plan on towing with my truck, but I'll probably only ever gross 13K max combined and that'll probably be a rarity.
I know after my quick 6 minute drive home my engine bay is like the surface of the sun.

Got a link to said radiator? Efan is better at an idle, engine driven is better when you're moving. One isn't better than the other at everything. Late Crown Vics came with both stock: an efan puller in front of the engine driven fan.

 

[BNielsen]

Got a link to said radiator? Efan is better at an idle, engine driven is better when you're moving. One isn't better than the other at everything. Late Crown Vics came with both stock: an efan puller in front of the engine driven fan.

https://www.coldcaseradiators.com/product/94-01-gm-truck-74l-aluminum-performance-radiator
Pricey, but I paid a little over $290 for my factory replacement NAPA rad.
I'm looking more and more at Flex-A-Lite's fan options and I'm finding some that are rated for 6800-7000 CFM now, I've got a Severe Service clutch and an S10 Fan but there's been quite a few times where it won't keep up with keeping the truck cool, everything is working correctly and coolant is topped up.

 

[Supercharged111]

https://www.coldcaseradiators.com/product/94-01-gm-truck-74l-aluminum-performance-radiator
Pricey, but I paid a little over $290 for my factory replacement NAPA rad.
I'm looking more and more at Flex-A-Lite's fan options and I'm finding some that are rated for 6800-7000 CFM now, I've got a Severe Service clutch and an S10 Fan but there's been quite a few times where it won't keep up with keeping the truck cool, everything is working correctly and coolant is topped up.

Spectra makes radiators for Napa and Advance. I got a Spectra off of Amazon for half of what Napa wanted and then, when I rammed a drill bit through that, got a replacement from Advance at 20% off online. How thick is your current radiator?

 

[BNielsen]

Spectra makes radiators for Napa and Advance. I got a Spectra off of Amazon for half of what Napa wanted and then, when I rammed a drill bit through that, got a replacement from Advance at 20% off online. How thick is your current radiator?

It's a little over 2 1/2 inches thick on the core of the rad, the plastic tanks measure out 3"

 

[Supercharged111]

It's a little over 2 1/2 inches thick on the core of the rad, the plastic tanks measure out 3"

Mine doesn't keep up well if I leave it idling forever and it's hot as balls, but if it's moving the temp is rock steady. That aftermarket sounds about the same size then as it has 2 1.25" cores. Under what conditions are you having cooling issues? I run 180 stats in both trucks BTW. Maybe try one of those and see how the truck does.

 

[L31MaxExpress]

Mechanical clutch fan does a much better job cooling my Express van than the 34" police tahoe dual fan setup I had on it before. I use a 0.057" ford orifice tube. A/C stays ICE cold even at idle. Cools about 38°F out of the vents at idle on a humid 105°F day here in Texas. On the highway it will get down to about 30-32°F before the compressor cycles off.

 

[Hogg]

Underdrive pulleys can make the issue of poor stoplight A/C performance worse than OEM.

The OEM GMT-400'like trucks in addition to the mechanical fan also come equipped for an "Aux. electric fan as well. Control for the AUX. fan is in the L29 calibration.

Even bumping the idle rpm a hundred or 2 rpm will help, but only really acceptable with non-stock(ie higher stall=looser) torque converters or manual trans trucks.

Here's the OEM GM Aux. electric fans. (notice how teh description staes that for the 5.0/5.7 engines its called an Aux fan, for the L29 its called a "A/C condenser fan)

Description:
"5.0 & 5.7L. Auxiliary. Incl.Fan Blade & Motor./7.4L, ac condenser fan"
https://www.gmpartsdirect.com/oem-parts/gm-engine-cooling-fan-assembly-15717423/?c=bT0x

peace
Hog

 

[Supercharged111]

Underdrive pulleys can make the issue of poor stoplight A/C performance worse than OEM.

The OEM GMT-400'like trucks in addition to the mechanical fan also come equipped for an "Aux. electric fan as well. Control for the AUX. fan is in the L29 calibration.

Even bumping the idle rpm a hundred or 2 rpm will help, but only really acceptable with non-stock(ie higher stall=looser) torque converters or manual trans trucks.

Here's the OEM GM Aux. electric fans. (notice how teh description staes that for the 5.0/5.7 engines its called an Aux fan, for the L29 its called a "A/C condenser fan)

Description:
"5.0 & 5.7L. Auxiliary. Incl.Fan Blade & Motor./7.4L, ac condenser fan"
https://www.gmpartsdirect.com/oem-parts/gm-engine-cooling-fan-assembly-15717423/?c=bT0x

peace
Hog

Holy crap, you're still alive! Haven't seen you since FSC and GMTC.

 

[L31MaxExpress]

Underdrive pulleys can make the issue of poor stoplight A/C performance worse than OEM.

The OEM GMT-400'like trucks in addition to the mechanical fan also come equipped for an "Aux. electric fan as well. Control for the AUX. fan is in the L29 calibration.

Even bumping the idle rpm a hundred or 2 rpm will help, but only really acceptable with non-stock(ie higher stall=looser) torque converters or manual trans trucks.

Here's the OEM GM Aux. electric fans. (notice how teh description staes that for the 5.0/5.7 engines its called an Aux fan, for the L29 its called a "A/C condenser fan)

Description:
"5.0 & 5.7L. Auxiliary. Incl.Fan Blade & Motor./7.4L, ac condenser fan"
https://www.gmpartsdirect.com/oem-parts/gm-engine-cooling-fan-assembly-15717423/?c=bT0x

peace
Hog

While the underdrive pulley can effect a/c my 25% has not and that is on a dual evaporator system. My idle has always been 700-750 rpm though both before and after the underdrive swap.