All-New 2021 Chevrolet Tahoe/Suburban and GMC Yukon/Yukon XL Have More Power, Capability, Content

The all-new 2021 Chevrolet Tahoe and Suburban and 2021 GMC Yukon and Yukon XL are ready to live up to their legendary nameplates and segment leadership. The fully redesigned models feature three different engine offerings – updated 5.3L and 6.2L V8s and an all-new 3.0L Duramax diesel – along with a standard 10-speed transmission and a new independent rear suspension. Based on the new full-size truck architecture, the vehicles boast a variety of standard safety features and infotainment and technology options.

The Tahoe/Suburban offers six trim choices: LS, LT, street-inspired RST, off-road Z71, Premier with premium equipment and technology, and High Country. (Fig. 1)

Fig. 1

The Yukon/XL is available in four trim levels: SLE, SLT, off-road AT4, and Denali. (Fig. 2)

Fig. 2


The 5.3L V8 engine (RPO L84) generates 355 horsepower and 383 lb.-ft. of torque. For those looking for more power, the 6.2L V8 engine (RPO L87) produces 420 horsepower and 460 lb.-ft. of torque. Both engines feature Dynamic Fuel Management, with more than 12 modes of cylinder deactivation to optimize engine efficiency in a broad range of driving applications, including when towing a trailer. Other engine technology includes automatic engine stop/start, direct injection, and variable valve timing.

Dynamic Fuel Management can deactivate any combination of cylinder valves, with millisecond-accurate torque control, to optimize fuel consumption. The cylinder deactivation system uses electrically operated valve lifter oil solenoid valves, bolted at each cylinder in the engine block valley below the intake manifold assembly, to control the application of engine oil pressure to the intake and exhaust valve lifters on the cylinders selected to deactivate.

The Dynamic Fuel Management solenoid requires a magnetic tool to remove the valve lifter oil solenoid valves. The tool helps gain leverage to remove the valve lifter oil solenoids from the block. Once installed on top of the solenoid, place your hand over the remover and solenoid with a finger under the solenoid. Twist while pulling up on the tool and the solenoid. (Fig. 3)

Fig. 3

The 3.0L Duramax inline 6-cylinder turbo-diesel (RPO LM2) – the only diesel offering in the full-size SUV segment – is rated at 277 horsepower and 460 lb.-ft. of torque. (Fig. 4) It features cast-in-place iron cylinder liners within the aluminum alloy engine block, a forged steel crankshaft and connecting rods, and blended silicon/aluminum pistons for outstanding durability.

Fig. 4

The 3.0L diesel engine is part of the Cylinder Set Strategy (CSS) family of engines, which deliver reduced friction, weight, and exhaust emissions. The turbocharger system includes an electronically operated wastegate valve that provides good low-end torque as well as high-end performance. The engine also incorporates a variable geometry turbocharger, active thermal management, automatic engine stop/start, a variable intake manifold, and a variable pressure oiling system.

The new active thermal management system helps the engine warm up and achieve its optimal engine temperature more quickly. The system eliminates the need for a conventional thermostat. A rotary valve system is used to distribute coolant through the engine. The mechanical water pump is mounted on the right side of the engine. Coolant flows from the mechanical water pump into the engine cylinder block and cylinder head. The pump also provides cooled coolant flow from the radiator directly to the engine coolant flow control valve, which is attached to the engine block under the intake manifold.

The 10L80 10-speed automatic transmission (RPO MQC) is a heavy-duty, electronically controlled transmission. It features an electronic shifter (Electronic Transmission Range Selector, or ETRS) located on the instrument panel. The Park, Neutral, and Low controls are push buttons. The Reverse and Drive controls are pull switches. (Fig. 5)

Fig. 5

The transmission architecture features a case with integral bell housing for enhanced powertrain stiffness. A unique off-axis pump drive design allows for very low mounting in the transmission. The Transmission Control Module (TCM) is externally mounted at the left front of the vehicle to the rear of the underhood fuse box.

New Foundation

The all-new chassis of the Tahoe/Suburban and Yukon/XL features an independent suspension and longer wheelbase, providing enhanced passenger accommodations, cargo capacity, and driving dynamics. The structure uses a mix of materials, including advanced high strength steel, high strength steel, steel, and aluminum.

Compared with the previous live axle design, the independent multilink rear suspension, which includes three lateral arms, a longitudinal arm, coil springs, and a stabilizer bar, helps isolate road variations for a better ride quality and steering responsiveness while still providing the capability requirements for full-size SUVs. (Fig. 6)

Fig. 6

In addition, the available Air Ride Adaptive Suspension and Magnetic Ride Control systems deliver enhanced body control and handling. The Air Ride Adaptive Suspension has automatic load-leveling and up to 4 inches (100 mm) of ride-height adjustment.

In highway driving, the system automatically lowers the ride height 3/4-inch (19 mm) to improve aerodynamics and fuel efficiency. A driver-selectable setting lowers the suspension 2 inches (51 mm) to aid passenger entry and exit when the vehicle is parked. Drivers can also raise the body for additional ground clearance when driving off-road by 1 inch (25 mm) at low speeds in 4WD HI, and an additional 1 inch (25 mm) at lower speeds in 4WD LO.

The brake system includes 4-wheel, 17-inch disc brake rotors as standard equipment. The brakes are equipped with a new brake pad lining wear sensor system and an electronic parking brake system. When the brake pad lining wear sensor system is active, brake pad life percentage is displayed on the Driver Information Center. (Fig. 7) When the system has determined that the brake pads need to be replaced, a message displays that may include mileage remaining. After replacing the brake pads, the axle brake pad life monitor reset learn must be performed.

It may be necessary to turn off the system if aftermarket brake pads without wear sensors are installed. When the system is turned off, the front and rear brake pad life percentages will not display.

Fig. 7

Safety Features

The Tahoe/Suburban and Yukon/XL offer 30 safety and driver convenience technologies. These include:

  • HD Rear Vision Camera and HD Surround Vision
  • Head-Up Display
  • Automatic Emergency Braking
  • Forward Collision Alert
  • Front Pedestrian Braking
  • Rear Pedestrian Alert
  • Lane Change Alert with Side Blind Zone Alert with enhancements for trailering
  • Lane Keep Assist with Lane Departure Warning
  • Front and Rear Park Assist
  • IntelliBeam automatic headlamp control
  • Hitch Guidance

Inside the Cabin

The interior features of the Tahoe/Suburban (Fig. 8) and Yukon/XL include larger displays and more connectivity options for all passengers.

Fig. 8

A 10-inch diagonal color touchscreen is standard on all models on the center of the instrument panel. Infotainment systems IOR, IOS, and IOT (with navigation) are available. The systems support wireless Android Auto and Apple CarPlay, which can be set up to automatically connect to a paired, compatible mobile phone.

An 8-inch diagonal configurable color instrument cluster and Driver Information Center is available. The uplevel cluster, available on Denali models (Fig. 9) and some other trim levels, features enhanced graphics with electronic gauges across the top of the screen.

Fig. 9

Rear seat passengers can enjoy an available rear seat media package with dual 12.6-inch diagonal LCD touchscreens. Each rear screen has independent connections so passengers can watch different content. Navigation points of interest also can be sent to the front infotainment screen.

The available Power Sliding Center Console can slide back up to 10 inches (254 mm) for expansive storage flexibility. (Fig. 10) The console slides back for access to an open space and an additional hidden drawer underneath the main storage bin. Moving the console back also increases access to the controls on the rear of the console for rear seat passengers.

Fig. 10

Vehicle Intelligence Platform

The Tahoe/Suburban and Yukon/XL are built on the next generation Vehicle Intelligence Platform (VIP). The advanced data communication platform has five times more data processing power than the current system and offers incredible speed for new technologies, vehicle health monitoring, over-the-air updates, and industry-leading cybersecurity protection.

Next generation networks include two-wire CAN buses and two wire Ethernet buses to ensure high speed data transfer and multiple single-wire LIN buses to exchange information between master control modules and other smart devices. Low speed General Motors Local Area Network (GMLAN) networks are eliminated. CAN buses are used where data needs to be exchanged at a high rate, primarily by a control device using the information to adjust a vehicle system, such as powertrain or body controls.


The Tahoe/Suburban and Yukon/XL offer many of the trailering technologies found on the Silverado and Sierra. The available trailering package includes a high-capacity radiator and cooling fan, an integrated trailer brake controller, and up to nine camera views. Plus, the available trailering app offers customization options for several trailer profiles, additional cameras, and trailer tire pressure and temperature monitoring.

PDI Instructions

During the Pre-Delivery Inspection, check the following special items:

  • To use the 110V A/C power outlet, at each new ignition cycle, push the 110V power button located on the left side of the instrument panel.
  • Enable the deployment function of the running boards by selecting the Settings icon on the Home Page of the infotainment screen. Go to Vehicle > Running Boards > Automatic Running Boards > Deploy Running Boards. Open any door and confirm the running board on that side of the vehicle deploys.
  • If the vehicle has the navigation system option (RPO IOT), ensure that the Nav SD card that is located beneath the USB hub in the armrest console is inserted correctly and is functional.

Special Tools

Tool Number

Tool Name


Installer, Pinion Seal and Side Bearing


Replacer, Pinion Bearing Cup


Replacer, RDM Mount Bushing


Spreader, RDM Rear Cover


Bridge, RDM Side Bearing Cap


Fixture, RDM Rotating


Remover, Axle Flange and Shaft


Installer, Pinion Seal


Installer, RH Output Seal


Installer, LH Output Seal

For much more information on the all-new 2021 Tahoe/Suburban and Yukon/XL, refer to Bulletin #20-NA-137.

– Thanks to Hassan Abdallah and Tom Renno

GM Service Know-How Emerging Issues
New 2021 Tahoe/Suburban and Yukon/Yukon XL Air Ride Adaptive Suspension

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