3.0L Duramax - who owns or has driven one

[DemonWorks]

Glad I saw you guys talking about the temps. Mine does it, I don't like it but GM says that's how it's designed !

 

I just did a quick video on my truck and the temp gauge moving is at 4:14

 

https://www.youtube.com/watch?v=6VCQJzpIadA

 

it does it all of the time ! Sits right above 210 and then goes up to just under 3/4 and then eventually comes down then does it again.

 

I tried it in tow and checkered flag mode and no change. I will be actually towing mid october and people say it actually runs cooler while towing, so I will see on that.

[Ojustracing]

12 hours ago, Carbon said:

Glad I saw you guys talking about the temps. Mine does it, I don't like it but GM says that's how it's designed !

 

I just did a quick video on my truck and the temp gauge moving is at 4:14

 

https://www.youtube.com/watch?v=6VCQJzpIadA

 

it does it all of the time ! Sits right above 210 and then goes up to just under 3/4 and then eventually comes down then does it again.

 

I tried it in tow and checkered flag mode and no change. I will be actually towing mid october and people say it actually runs cooler while towing, so I will see on that.

It actually runs cooler when towing because the truck is trying to lower the oil temps!!!!! neat to watch when you use an app/idash. 

[tayhadagti]

On 9/29/2020 at 9:40 AM, Ojustracing said:

It actually runs cooler when towing because the truck is trying to lower the oil temps!!!!! neat to watch when you use an app/idash. 

I noticed this when I towed my boat about 90 miles each way.  It was never increasing the temp over 210 like it does other times.  

[redwngr]

From a year ago. 

There is a section with some cooling system info.

 

https://gm-techlink.com/?p=12050

 

New Duramax Diesel 3.0L 6-Cylinder Engine Powers Up Silverado 1500, Sierra 1500

September 13, 2019

The all-new Duramax^® Diesel 3.0L inline 6-cylinder turbocharged engine (RPO LM2) delivers plenty of power — producing 282 horsepower and 450 lb.-ft. of torque — along with impressive fuel economy — an estimated 30 mpg (7.8L/100km) highway on 2WD models — in an efficient package. (Fig. 1) Available on 2020 Silverado 1500 and Sierra 1500 models, it’s paired with the 10L80 10-speed automatic transmission (RPO MQB).

 

Fig. 1

 

Turbocharged Performance

The dual overhead camshaft (DOHC) engine uses an aluminum block with six pressed-in iron sleeves and a high pressure diesel fuel injection system. The lower oil pan is made of dual-layer stamped aluminum. (Fig. 2)

The 3.0L diesel engine uses SAE 0W-20 dexosD diesel engine oil. Do not add anything to the oil.

 

Fig. 2

 

The turbocharger is a variable nozzle design with an electric vane actuator attached to the exhaust manifold. The Variable Geometry Turbine (VGT) body assembly contains a contact-less inductive VGT position sensing element that is managed by a customized integrated circuit. The VGT position sensor provides a signal voltage that changes relative to the VGT vanes angle. The customized integrated circuit translates the voltage based position information into serial data using Single Edge Nibble Transmission (SENT) protocol. The VGT position sensor information is transmitted between the VGT body and the Engine Control Module (ECM) on the signal/serial data circuit. The ECM decodes the serial data signal and is used as voltages for the VGT position sensor.

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)

 

Fig. 3

 

The fuel system features a 3-phase electric fuel pump in the fuel tank that is controlled by the fuel pump driver control module and the ECM. Fuel is pumped from the fuel tank to the fuel filter assembly, which consists of a fuel filter/water separator, fuel heater, fuel temperature sensor, and a water in fuel sensor.

The ECM controls the fuel injection timing and has the ability to learn injector timing performance. Under the correct operating conditions, the ECM will pulse each injector individually and measure the changes in rotational speed of the crankshaft using the input from the crankshaft position sensor. The ECM will run this diagnostic at one fuel rail pressure operating point for each injector. The ECM stores the injector timing value.

 

Active Thermal Management

The Active Thermal Management (ATM) system on the 3.0L diesel engine distributes coolant through the engine in a targeted manner, sending heat where it’s needed to warm up the engine and reduce friction. It also promotes quicker heating of the passenger compartment and enhanced engine cooling during high power operation. The system uses a conventional engine-driven coolant pump while the ECM controls the ATM system using feedback from various coolant temperature sensors.

The engine coolant flow control valve assembly that is part of the ATM system uses two chambers to control coolant flow. (Fig. 4) The first chamber controls the coolant flow rate across the radiator and bypass. The second chamber controls the flow to the transmission and engine oil cooler as needed, providing heated coolant from the EGR/turbocharger return circuit or cold coolant directly from the pump outlet.

 

Fig. 4

 

Exhaust Aftertreatment System

The exhaust aftertreatment system is designed to reduce the levels of hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), and particulate matter (PM) pollutants remaining in the engine’s exhaust gases before they exit via the vehicle’s exhaust tailpipe. NOx is controlled by a Selective Catalytic Reduction (SCR) converter combined with precise injections of Diesel Exhaust Fluid (DEF), while PM is controlled by a diesel particulate filter (DPF). To reduce packaging volume and manufacturing cost, the SCR catalyst on the DPF is coated to form an SCR-coated DPF, or a Selective Catalytic Reduction on Filter (SCRoF). The close coupled DOC along with the SCR on Filter are integrated into one assembly.

In the DPF, particulate matter consisting of extremely small particles of carbon remaining after combustion are removed from the exhaust gas by the large surface area of the DPF. DEF is injected into the exhaust gases prior to entering the SCRoF stage. Within the SCRoF, NOx is converted to nitrogen (N2), carbon dioxide (CO2), and water vapor (H20) through a catalytic reduction fueled by the injected DEF.

The exhaust aftertreatment system components (Fig. 5) include:

1. Exhaust temperature sensor
2. DEF injector mounting flange
3. Exhaust pressure differential sensor pipe
4. Exhaust pressure differential sensor pipe
5. EGR flange
6. NOx catalytic converter assembly
7. Particulate matter boss
8. Exhaust back pressure valve

 

Fig. 5

 

The DEF fill, identified by a blue cap, is located behind the fuel fill door. (Fig. 6) After filling the DEF tank, unless the DEF tank was empty, there may be a short delay before the increased fluid level is detected and the DEF level indicated on the Driver Information Center is updated.

 

Fig. 6

 

Automatic Engine Stop/Start System

Designed to help conserve fuel, the Automatic Engine Stop/Start system may turn off the engine when the brakes are applied and the vehicle is at a complete stop, if the required operating conditions are met. The tachometer will read Auto Stop.

The Stop/Start system can be disabled and enabled by pressing the Stop/Start switch on the center of the instrument panel. (Fig. 07) The system is enabled each time the vehicle is started.

 

Fig. 7

 

An auxiliary electric engine coolant pump motor (Fig. continually circulates engine coolant through the heater core while the Stop/Start system has shut down the engine and the ambient temperature is colder than 59°F (15°C) to maintain the passenger compartment temperature.

 

Fig. 8

 

The 3.0L diesel engine also features an active engine mount system to enable an optimal balance between vehicle Noise Vibration and Harshness (NVH) performance and vehicle dynamics, including during Automatic Engine Stop/Start events. There is a single solenoid on each active engine mount that is energized during an ignition event and switched on for idle and driving events. The solenoid valves are supplied with battery voltage through a single fuse and are controlled by the ECM.

 

Normal Sounds After Engine Shut-Off

After the 3.0L diesel engine has been shut off, several sounds may be heard in the engine bay. These sounds may be caused by the following components performing a cleaning cycle:

• Turbocharger linkage (Fig. 9)
• Exhaust throttle valve
• Intake manifold swirl valve

 

Fig. 9

 

The sounds are normal operating characteristics of the vehicle and do not impact the designed performance or reliability of the vehicle.

Refer to Bulletin 19-NA-188 for additional information.

[AlexB]

I have 10k miles on my 2020 3.0.  It has the towing package, LT trim, MT tires, 3.73 gears.  I dont get the 30mpg you guys are getting or others.  Not sure how slow you're driving and what gears you have.   As far as temps, I just drive.  Its under warranty.  I've towed my boat and Camaro on a trailer in the  Texas heat but I dont recall seeing the temps you guys do.  I think it stays around 210 all the time.

[Ojustracing]

16 hours ago, AlexB said:

I have 10k miles on my 2020 3.0.  It has the towing package, LT trim, MT tires, 3.73 gears.  I dont get the 30mpg you guys are getting or others.  Not sure how slow you're driving and what gears you have.   As far as temps, I just drive.  Its under warranty.  I've towed my boat and Camaro on a trailer in the  Texas heat but I dont recall seeing the temps you guys do.  I think it stays around 210 all the time.

228 F

[yousaveone]

Mine runs above 210 and way below depending on something. The truck get 32mpg when there is no wind and ideal circumstances. Put a trailer on it and mileage goes to 20; even the smallest trailer. I can see how the 3.73 gears could change mileage. Great engine but it is a tiny 3.0. I guess we'll see how it holds up, I'm at 32K and going strong.

[Rubyralph]

On ‎10‎/‎17‎/‎2020 at 10:06 AM, AlexB said:

I have 10k miles on my 2020 3.0.  It has the towing package, LT trim, MT tires, 3.73 gears.  I dont get the 30mpg you guys are getting or others.  Not sure how slow you're driving and what gears you have.   As far as temps, I just drive.  Its under warranty.  I've towed my boat and Camaro on a trailer in the  Texas heat but I dont recall seeing the temps you guys do.  I think it stays around 210 all the time.

What kind of Highway MPG do you get with the 3.73 gears?

 

Most others that are getting 30 MPG highway unloaded have the 3.23 gears like mine.

I think your truck has the "diesel off-road" package?

Thanks

[AlexB]

1 hour ago, Rubyralph said:

What kind of Highway MPG do you get with the 3.73 gears?

 

Most others that are getting 30 MPG highway unloaded have the 3.23 gears like mine.

I think your truck has the "diesel off-road" package?

Thanks

Yea, I thought that was it.  Just wanted to confirm.  Thanks!

[Rubyralph]

What highway MPG do you get and what’s your RPM @ 70 MPH?

thanks Ralph 

[BurnsMax]

8 hours ago, Rubyralph said:

What highway MPG do you get and what’s your RPM @ 70 MPH?

thanks Ralph 

Depends on the road but I usually get 20-23 MPG at that speed and it usually runs 1400-1500 RPM

[Sqrls]

2 hours ago, BurnsMax said:

Depends on the road but I usually get 20-23 MPG at that speed and it usually runs 1400-1500 RPM

I’m curious how much of that mpg difference is due to the gearing vs how much the larger duratracs hurt the mpg. 

[BurnsMax]

10 hours ago, Sqrls said:

I’m curious how much of that mpg difference is due to the gearing vs how much the larger duratracs hurt the mpg. 

I'm sure some it has to do with the 10 speed.  Not sure on the tires.  I don't have stock rims or tires on mine. 

[Sqrls]

7 hours ago, BurnsMax said:

I'm sure some it has to do with the 10 speed.  Not sure on the tires.  I don't have stock rims or tires on mine. 

I thought all the 3.0 diesels had the 10 speed? I should have been more clear in my question. The 3.73 gears for the 3.0 are only available with the diesel off road package if I’m correct. That package includes duratracs with the 3.73 gears that aren’t on any of the other diesels. From what I’ve seen, most of us with 3.23 gears get high 20s low 30s mpg at 70mph, but none of the 3.23 geared trucks come with duratracs.

 

So out of the 7ish mpg difference, I was curious how much off that loss is attributed to the heavier, knobbier tires and how much of it is from the gearing. I’m honestly surprised that it’s such a large difference in mpg.

[BurnsMax]

16 minutes ago, Sqrls said:

I thought all the 3.0 diesels had the 10 speed? I should have been more clear in my question. The 3.73 gears for the 3.0 are only available with the diesel off road package if I’m correct. That package includes duratracs with the 3.73 gears that aren’t on any of the other diesels. From what I’ve seen, most of us with 3.23 gears get high 20s low 30s mpg at 70mph, but none of the 3.23 geared trucks come with duratracs.

 

So out of the 7ish mpg difference, I was curious how much off that loss is attributed to the heavier, knobbier tires and how much of it is from the gearing. I’m honestly surprised that it’s such a large difference in mpg.

Gotcha.  Yes they all do come with a 10 speed.  I wasn't thinking about the hard to find 3.73 gears.  Mine has the 3.23s, I think I have only seen one person with the 3.73s