redwngr

Still only available on the 1500's.

Not much difference between them in the HD world. In the 1500's the AT4 gets the 2" lift, and the Denali gets the adaptive ride control suspension. Most of the rest seems to be appearance things -- both inside and outside. Both have a bunch of options that can be added to them. Colour choice can make a big difference in how chrome or painted or blacked out 'fits' the vehicle. Previous generation, Denali was equipped with a 'Denali only' drivers information centre and gauges display. (gauges were on the information screen, and the computer replaced on of them with a trans temp gauge when tow/haul was enabled; other trims had hardware gauges - trans temp could be displayed, but not as a gauge) I'm not actually sure about differences (or not) in the current HD trucks dash set-ups.

It'll be interesting to see the electric Hummer rollout that is due to begin this month.

Don't forget that the dmax comes with a 100,000 mile 5/yr powertrain warranty. Bumper to bumper is 36K, like the gassers. Pretty good bet that the time most of use get by 100,000 miles on one we will already have some good info on how they are performing with that many miles.

They've shown the update to the bed view that now includes zoom for MY2021. There is a video floating around showing how it works.

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: Exhaust temperature sensor DEF injector mounting flange Exhaust pressure differential sensor pipe Exhaust pressure differential sensor pipe EGR flange NOx catalytic converter assembly Particulate matter boss 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.

Offered on 2020 and 2021 1500 Silverado -- LT and RST trims only B4U Diesel Off-Road Package, includes (GT4) 3.73 axle ratio, (R3O) LT275/65R18C MT Goodyear Wrangler DuraTrac blackwall tires and (VOZ) Tri-fold hard tonneau cover, LPO LT - Requires 4WD model, (LM2) Duramax 3.0L Turbo-Diesel I6 engine and (Z71) Z71 Off-Road Package. Crew Cab models include (BVT) Chrome assist steps. Not available with (NHT) Max Trailering Package, (VYU) Snow Plow Prep Package, (PDZ) Z71 Off-Road and Protection Package, (RD4) 20" aluminum wheels with Argent metallic pockets, (QAB) or (QAE) tires, or any other assist step or tonneau cover. RST - Requires CK10743 Crew Cab Standard Bed 4WD model, (LM2) Duramax 3.0L Turbo-Diesel I6 engine and (Z71) Z71 Off-Road Package. Includes (BVT) Chrome assist steps. Not available with (STH) Rally Edition, (NHT) Max Trailering Package, (PDZ) Z71 Off-Road and Protection Package, (RD4) 20" aluminum wheels with Argent metallic pockets, (QAB) or (QAE) tires, or any other assist step or tonneau cover.

From the GM techlink article: Segmented DEF Level Gauge The current 2020 Silverado 1500 and Sierra 1500 models have a DEF level gauge on the instrument cluster that provides drivers with a representation of how much DEF is in the DEF tank up. (Fig. 2) The DEF level gauge does not operate like a typical float-style gauge that is used in a fuel tank. The Engine Control Module (ECM) monitors the DEF level and consumption rate in order to calculate an estimated range. DEF levels are detected by the DEF level sensor. There may be some fluctuation in the amount of DEF represented on the DEF level gauge. After filling the DEF tank, it may take a few key cycles to register the correct amount in the DEF tank. With the new segmented DEF level gauge, it is possible that after adding 5 gallons (18.9 L) of DEF that the gauge reads as a full tank after the fill event. However, if the actual level of DEF is just entering the last segment on the gauge, the gauge is likely to drop by one segment shortly after driving after the fill event. As a result, a driver could have an initial impression that the vehicle consumes an excessive amount of DEF.

Fill the def tank so you can do a hand calculated calculation of what it uses. Despite what the range/level def indicator may say, it is common for def tanks not to get filled before delivery. The only way to know it was full, so you an accurately check usage, is to top it up and record the odometer reading -- and later repeat. Def usage should be in direct ratio to the amount of fuel used. (somewhere around 2 gal def per 100 gallons of fuel) If change in vehicle usage results in twice as much fuel being used, it will also use twice as much def. Def is available everywhere that diesel is available. (if a station is really low diesel volume and doesn't have def, then it's not a place that I would be buying diesel) If it starts giving def level warnings get some def at the next fuel stop.

Drifting from the original question, but... 2020 3500 DRW High Country uses RS7 Wheels, 17" (43.2 cm) forged polished aluminum On HC - Requires dual rear wheels. 3500 SRW uses the same wheel as the 2500: PYS NEW! Wheels, 20" (50.8 cm) polished aluminum, 16-spoke HC - Requires single rear wheels.

Tow/haul mode raises the shift points, to reduce the amount of shifting back and forth. It also enables tow/haul grade braking which enhances the way the engine and transmission wok together to help maintain speed when running downhill. Tow/haul grade braking does not come on if the trans is in manual mode.

In 2019, gm said they have 4,100 dealers in the USA. https://www.gm.com/our-company/us.html#:~:text=In 2019%2C there were more,Motors dealers in the U.S. Canada has about 10% of that, say +/- 450. Lets assume 4500 dealers in total. 1200 per day x 5 days = 6000 (7200 if the build 1200 more on weekend) 6000/4500 = 1.3 trucks per dealer per week... (1.6 per dealer if they build 1200 on weekends) Assuming that dealers are still trying to sell the ones available, it'll take a long time to go current 'low' inventory to the fullish lots from before last fall's strike and the winter/spring covid shutdown. We've done a bunch of road tripping the last week or so. I find it quite amazing the number of dealers we've been by that I know had crammed full lots in late summer 2019, that have huge amounts of empty space this week. They're even parking them further apart than usual to make it look like there is more there. It's not just new HD trucks that are in short supply. And not just GM lots that have thinned out. It'll be interesting to see where this goes.

When the fuel usage is increased (like when towing) the def use will also increase, by about the same percentage.

How fast are you pulling the trailer? Flat deck or enclosed utility or camper or .../? How tall is it?

Order guide seems to indicate that all 2020 AT4's are 3.23 (same for 2021)

If they sold the Yenko cheap, it would not longer be an exclusive club... Like most 'sport' vehicles the 'look at this thing factor'.

Tapping the brake the second time and the ecm figures you want more braking. If ECM/exhaust brake can request the TCM perform a downshift if/when extra braking is required. (if the trans is in M mode, the computers won't do an automatic downshift) Exhaust brake and transmission grade braking will also do their thing to prevent speed-up above a set cruise control speed.

The DEF gauge is NOT a simple variable gauge like a fuel gauge. It also blends in an estimate of the remaining range (like the range estimate for fuel in the dic). The only way to know miles per def gallon is to fill it, drive it for a few thousand and refill it. Just like a hand-calc for fuel mileage. https://gm-techlink.com/?p=13143 Diesel Exhaust Fluid Consumption May 21, 2020 The diesel engines (RPOs LWN, LM2, L5P, L5D) available on 2020 Colorado, Express, Silverado 1500, Silverado 2500HD/3500HD, Silverado 4500HD/5500HD/6500HD, Canyon, Savana, Sierra 1500, and Sierra 2500HD/3500HD models use Diesel Exhaust Fluid (DEF) (Fig. 1) in order to reduce the exhaust Oxides of Nitrogen (NOx) levels within the Selective Catalyst Reduction stage of the exhaust aftertreatment system. A series of driver prompts and warnings are initiated when the DEF level falls below a calibrated value. Fig. 1 Segmented DEF Level Gauge The current 2020 Silverado 1500 and Sierra 1500 models have a DEF level gauge on the instrument cluster that provides drivers with a representation of how much DEF is in the DEF tank up. (Fig. 2) The DEF level gauge does not operate like a typical float-style gauge that is used in a fuel tank. The Engine Control Module (ECM) monitors the DEF level and consumption rate in order to calculate an estimated range. DEF levels are detected by the DEF level sensor. Fig. 2 There may be some fluctuation in the amount of DEF represented on the DEF level gauge. After filling the DEF tank, it may take a few key cycles to register the correct amount in the DEF tank. With the new segmented DEF level gauge, it is possible that after adding 5 gallons (18.9 L) of DEF that the gauge reads as a full tank after the fill event. However, if the actual level of DEF is just entering the last segment on the gauge, the gauge is likely to drop by one segment shortly after driving after the fill event. As a result, a driver could have an initial impression that the vehicle consumes an excessive amount of DEF. Emissions Requirements Every year, GM produces diesel engines that continue to meet aggressive federal requirements to reduce Nitrogen Oxides (NOx) in the vehicle exhaust. As DEF is required to reduce the NOx in the exhaust, DEF consumption will increase as NOx reduction requirements increase. Customer trading in an older model year diesel vehicle for a newer model year vehicle will likely see an increase in DEF usage. DEF consumption increases as the newer vehicles meet the more stringent emission requirements for that model year. The amount of DEF consumed also is a function of how hard the engine is working, or engine load. Due to engine use, it is more representative to compare DEF consumption to the amount of fuel consumed – also a function of engine load – instead of miles traveled. In addition to engine load, other factors that affect the DEF usage rate are the humidity, temperature, and altitude where the vehicle is operating. Under certain conditions, the ECM will increase or decrease the amount of DEF used based on learning or adaptive algorithms. In the event of a malfunction and Check Engine light, the ECM may double or even eliminate the amount of DEF that is being used. An improper amount of DEF use will continue until the vehicle is repaired and the learned value in the ECM is reset.

And it's a 'Denali 'only' colour, which is that info was included in the post.

Colours in those posts were just the ones that changed for 2021. These are 2021 HD colours: (names are the GMC ones, Chev will have the same RPO codes, but often uses different names.) As per usual, Chev does not use the the 'Denali only' colours White Frost Tricoat G1W Cardinal Red G7C Pacific Blue Metallic GA0 Quicksilver Metallic GAN Summit White GAZ Onyx Black GBA Carbon Black Metallic GCI Brownstone Metallic GNK NEW! Ebony Twilight Metallic GB8 NEW! Cayenne Red Tintcoat GSK NEW! Hunter Metallic GED Most are 'extra charge'. Some are not available on all trims. White Frost - Not available with (4SB) AT4 Trim. Cardinal Red - Not available on (4SB) AT4 or (5SA) Denali. Carbon Black Metallic - Not available after December 2020. Requires (5SA) Denali. Brownstone Metallic - Not available on (5SA) Denali. Ebony Twilight Metallic - Required with (JSE) Denali Black Diamond Edition. Hunter Metallic - Requires (5SA) Denali. Not available until January 2021.

For 2021, Wireless Phone Projection, for Apple CarPlay and Android Auto is standard on LTZ and HC. Z45 Suspension, Adaptive Ride Control On HC - Required and only available with (PDM) High Country Deluxe, (RVA) 22" x 9" polished aluminum wheels or 22" LPO wheels. PDM High Country Deluxe, includes (PDJ) Safety Package II, (CF5) power sunroof, (RVA) 22" polished aluminum wheels, (XCE) 275/50R22SL all-season, blackwall tires and (RIA) floor liner, LPO On HC - Requires (Z45) Adaptive Ride Control. Not available with (Z71) Z71 Off-Road Package. (RVA) 22" polished aluminum wheels may be upgraded to (SEV) 22" 6-spoke Low Gloss Black wheels with machined accents, LPO, (SEW) 22" 5-spoke Dark Silver aluminum wheels with Chrome, LPO, (SF0) 22" Bright Chrome wheels, LPO or (SGM) 22" High Gloss Black wheels, LPO. Looks like Adaptive Ride control requires PDM, which is not available if Z71 was ordered. (so it seems 'fully loaded' still has choices...)

Same deal with the 'burb and Tahoe. Z71 is 5.3 only. 6.2 is only available in the HC.

OM says 87 for all gasoline engines except the 6.2 which it recommends 93.

No, but the dealers can price and accept orders for the 2021's. Even if you decide to buy something currently at a dealer, be sure to check out the advertising on the trailering feature improvements for 2021's to see if any of them are important to you. Nothing worse that having one home for few weeks and then finding out the there is some desirable feature that was available a few weeks after the purchase.

The def indicator is also trying to estimate range remaining - so 'recent' rate of usage is included in the estimate. Similar to the 'range' estimate for fuel. DEF usage is a percentage of fuel usage, so when fuel usage is unusually high so is def usage. Up and down the Loveland Pass means big swings in usage. The combo of 'level' and 'range' indicator certainly seems to be causing concern for many operators. Be sure to read the section about the DEF gauge: https://gm-techlink.com/?p=13143 Diesel Exhaust Fluid Consumption May 21, 2020 The diesel engines (RPOs LWN, LM2, L5P, L5D) available on 2020 Colorado, Express, Silverado 1500, Silverado 2500HD/3500HD, Silverado 4500HD/5500HD/6500HD, Canyon, Savana, Sierra 1500, and Sierra 2500HD/3500HD models use Diesel Exhaust Fluid (DEF) (Fig. 1) in order to reduce the exhaust Oxides of Nitrogen (NOx) levels within the Selective Catalyst Reduction stage of the exhaust aftertreatment system. A series of driver prompts and warnings are initiated when the DEF level falls below a calibrated value. Fig. 1 Segmented DEF Level Gauge The current 2020 Silverado 1500 and Sierra 1500 models have a DEF level gauge on the instrument cluster that provides drivers with a representation of how much DEF is in the DEF tank up. (Fig. 2) The DEF level gauge does not operate like a typical float-style gauge that is used in a fuel tank. The Engine Control Module (ECM) monitors the DEF level and consumption rate in order to calculate an estimated range. DEF levels are detected by the DEF level sensor. Fig. 2 There may be some fluctuation in the amount of DEF represented on the DEF level gauge. After filling the DEF tank, it may take a few key cycles to register the correct amount in the DEF tank. With the new segmented DEF level gauge, it is possible that after adding 5 gallons (18.9 L) of DEF that the gauge reads as a full tank after the fill event. However, if the actual level of DEF is just entering the last segment on the gauge, the gauge is likely to drop by one segment shortly after driving after the fill event. As a result, a driver could have an initial impression that the vehicle consumes an excessive amount of DEF. Emissions Requirements Every year, GM produces diesel engines that continue to meet aggressive federal requirements to reduce Nitrogen Oxides (NOx) in the vehicle exhaust. As DEF is required to reduce the NOx in the exhaust, DEF consumption will increase as NOx reduction requirements increase. Customer trading in an older model year diesel vehicle for a newer model year vehicle will likely see an increase in DEF usage. DEF consumption increases as the newer vehicles meet the more stringent emission requirements for that model year. The amount of DEF consumed also is a function of how hard the engine is working, or engine load. Due to engine use, it is more representative to compare DEF consumption to the amount of fuel consumed – also a function of engine load – instead of miles traveled. In addition to engine load, other factors that affect the DEF usage rate are the humidity, temperature, and altitude where the vehicle is operating. Under certain conditions, the ECM will increase or decrease the amount of DEF used based on learning or adaptive algorithms. In the event of a malfunction and Check Engine light, the ECM may double or even eliminate the amount of DEF that is being used. An improper amount of DEF use will continue until the vehicle is repaired and the learned value in the ECM is reset.