Grill Shutters

kodiakdenali · December 14, 2020

Does anyone know what the function of these are? Are they to help heat up the engine faster and only close while the engine is cold? Are they for aerodynamics and close at highway speeds even when up to operating temps? or both?

I'm asking because (I haven't seen how it's installed yet) but I'm wondering what affect these have on an intercooler. I have to assume it will be in front of the shutters, but even so if they close it will reduce the airflow "outlet" and might reduce airflow over the intercooler.

Z45 · December 14, 2020

From GM

Active Aero Shutters are a General Motors active aerodynamics technology that improve the aerodynamic performance and maximize aerodynamic efficiency of a vehicle in order to deliver better fuel economy.

redwngr · December 14, 2020

for the 3.0

The intake manifold houses the integrated intercooler. The intercooler system includes an air cooler/heat exchanger built into the intake, a charge air cooler (CAC) radiator assembled in the front fascia, and an electric coolant pump. The CAC coolant pump provides operational and diagnostic feedback to the ECM. (Fig. 3)

kodiakdenali · December 14, 2020

45 minutes ago, elcamino said:

From GM

Active Aero Shutters are a General Motors active aerodynamics technology that improve the aerodynamic performance and maximize aerodynamic efficiency of a vehicle in order to deliver better fuel economy.

so definitely may close at higher speeds when a smaller grill opening is still sufficient to keep the engine cool. I may need to ask some qeustions about this.

kodiakdenali · December 14, 2020

15 minutes ago, redwngr said:

for the 3.0

The intake manifold houses the integrated intercooler. The intercooler system includes an air cooler/heat exchanger built into the intake, a charge air cooler (CAC) radiator assembled in the front fascia, and an electric coolant pump. The CAC coolant pump provides operational and diagnostic feedback to the ECM. (Fig. 3)

I hadn't thought of that, the 3.0 is certainly intercooled also so the factory must have considered that and made sure their solution wouldn't be affected.

In my case its a 6.2, and I'm talking about an aftermarket intercooler.

newdude · December 14, 2020

2 hours ago, kodiakdenali said:

Does anyone know what the function of these are? Are they to help heat up the engine faster and only close while the engine is cold? Are they for aerodynamics and close at highway speeds even when up to operating temps? or both?

I'm asking because (I haven't seen how it's installed yet) but I'm wondering what affect these have on an intercooler. I have to assume it will be in front of the shutters, but even so if they close it will reduce the airflow "outlet" and might reduce airflow over the intercooler.

The 2.7Turbo is intercooled and uses the shutter sysetm. 3.0 diesel does as well but the intercooler is on the top of the engine, but the coolant through it goes to an aux radiator up front. 5.3 with plow prep deletes the shutters for max airflow when a plow is installed.

What you might want to look into is seeing if you can mount a cooler down low. The 2.7T and 3.0 Diesel use a front lower fascia that is opened up under the license plate bracket for extra air flow. Both those engine options have a dual shutter system, so the upper main one and a lower aux shutter that controls air flow to the aux radiator for the intercooler.

Description and operation from GM below. To control these if its possible, you will most likely need to be on a modded ECU from HP Tuners:

Quote

Active Grille Air Shutter Description and Operation

The active grille air shutter system closes shutters in the front grille to enhance vehicle aerodynamics in driving situations where cooling and A/C loads are relatively low and high levels of front end airflow are not required. If high levels of airflow are required the active grille air shutter system will open one or both shutters. The control signal from the engine control module, ignition and ground circuits enable the active grille air shutter actuators to operate. If the conditions for opening the shutters are reached the engine control module commands the active grille air shutter actuators to open one or both shutters.

The dual active grille air shutter system consists of two aero shutter mechanisms located in the front grille for controlling the amount of air flowing through the grille. It includes three wires; ground, power and a Local Interconnect Network (LIN) Bus serial data circuit from the engine control module to the shutter actuator. The engine control module determines shutter state based on various vehicle conditions such as vehicle speed, coolant temperature, fan state, refrigerant system pressure, A/C compressor state and ambient temperature. The engine control module has the ability to command each shutter individually to the open or closed positions through communications on the LIN Bus.

The actuators are powered by an ignition circuit that is active when the key is in the RUN position. The vehicle may have to be driven for up to 13 minutes at speeds greater than 41 km/h (25 mph) before a shutter begins to move. If low ambient temperature is detected, the shutters will remain in the closed position.

Here is a pic of the dual shutter setup. I red boxed the aux radiator and the lower shutters.

Pic of the fascia:

Edited December 14, 2020 by newdude

redwngr · December 14, 2020

23 minutes ago, kodiakdenali said:

I hadn't thought of that, the 3.0 is certainly intercooled also so the factory must have considered that and made sure their solution wouldn't be affected.

In my case its a 6.2, and I'm talking about an aftermarket intercooler.

iirc, there is a poster that works for the company that supplies the shutters, and posted that there is nothing that detects that they opened or closed after being commanded to do so --- so for an aftermarket / high performance application it would be possible to trim the slats to suit.

kodiakdenali · December 14, 2020

13 minutes ago, newdude said:

The 2.7Turbo is intercooled and uses the shutter sysetm. 3.0 diesel does as well but the intercooler is on the top of the engine, but the coolant through it goes to an aux radiator up front. 5.3 with plow prep deletes the shutters for max airflow when a plow is installed.

What you might want to look into is seeing if you can mount a cooler down low. The 2.7T and 3.0 Diesel use a front lower fascia that is opened up under the license plate bracket for extra air flow. Both those engine options have a dual shutter system, so the upper main one and a lower aux shutter that controls air flow to the aux radiator for the intercooler.

Description and operation from GM below. To control these if its possible, you will most likely need to be on a modded ECU from HP Tuners:

thanks!

I have looked at and considered the alternate lower insert, I think it might be worth replacing. actually doesn't look too difficult to remove, plus my stock one is chrome anyway and the dealer drilled it to install a front plate bracket. I removed the bracket, patched the holes, and plastidipped it, but I sure wouldn't mind just getting a replacement. this might be another motivator.

I will be running an HPTuners ECU

kodiakdenali · December 14, 2020

2 minutes ago, redwngr said:

iirc, there is a poster that works for the company that supplies the shutters, and posted that there is nothing that detects that they opened or closed after being commanded to do so --- so for an aftermarket / high performance application it would be possible to trim the slats to suit.

I've seen his posts before, I will keep that in mind. I'd like to keep the functionality of the shutters if I can, as long as it doesn't interfere with intercooler functionality. I still don't know for sure where it mounts, I wonder if it could mount way down at the bottom of the front end where the 2.7L/3.0L lower grill insert with the additional wide opening could provide it with plenty of air.