Thirteen recalls and 295 complaints in the first year of a brand-new truck — buyable, but only with the whole campaign history in hand.

A recurring and unusually specific thread in this year's file: owners whose 6.2L failed exactly the way the recalled trucks fail, and whose VIN was not included. "Engine failure causing vehicle to be unsafe to drive. Our vehicle was not included in the L-87 loss of propulsion GMC recall even though it is a 2021 Yukon 6.2L. The engine failure is same as those being recalled." Another owner reports the failure involving "the camshaft, lifters, and crankshaft" after "engine ticking and knocking noises, rough idle, loss of power." A third was told by his mechanic that he "knew there was a recall for similar 2021 Yukon engine issues but for some reason this model was not included." Do not assume a 2021 6.2L is covered because the model year is. Check the VIN against 25V274 specifically and get the answer in writing.

The ten-speed's control valve wears and loses hydraulic pressure, producing harsh shifting, a service-engine-soon message, reduced performance and diagnostic code P0747. Owners describe shuddering at 50 to 60 mph, limp mode capping the truck at 30 mph, and outright failure at 110,000 well-maintained miles. On the 2021 diesel this is safety recall 24V797, a free software update, and GM says it will "provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a defective control valve." On every 2021, GM's Special Coverage for the control valve runs fifteen years or 150,000 miles and pays for a new valve body. This is the rare case where the noisy year is the protected one. Drive for shudder and harsh shifts, and ask whether the valve body has been replaced.

Most GM campaigns sweep the whole full-size family. Two on this model year do not, and both are short-wheelbase-only. Recall 21V064 covers 2021 Tahoe and Yukon vehicles whose "fuel tank assemblies may be missing adhesive between two layers of the fuel tank shell which may result in a fuel leak" — a fire risk in the presence of an ignition source, remedied by replacing the tank free. Recall 21V579 covers 2021 Tahoe and Yukon vehicles where "dealer service technicians may have calibrated the brake system incorrectly, affecting Electronic Stability Control, traction control, Anti-Lock Brake System, and braking while towing a trailer"; the module is recalibrated free. A community source describes the second from the owner side — brake feel and pressure lost intermittently with the ABS, stability-control and trailer-brake lights coming on together.

Two more launch-year campaigns cover ways this truck can stop helping you. Recall 21V739 covers a fuel-pump power control module that can make the pump fail or run intermittently, interrupting fuel flow and stalling the engine unexpectedly; dealers replace the module free. Recall 21V455 covers a software fault that can cause a loss of power steering assist at startup or while driving, fixed by a dealer or over the air. A community source confirms the steering problem was traced to a software bug and fixed under a factory campaign. Both are free and both are quick, but they are separate campaigns with separate completion records — verify each by VIN rather than asking whether "the recalls" were done.

The launch produced an unusual cluster of restraint campaigns covering different failures, so each needs checking separately. 20V811 covers incorrect bolts used at one or more belt fastening locations. 21V190 covers third-row outboard belts entrapped or misrouted behind the seat-folding mechanism, which damages the webbing. 22V617 covers a third-row buckle retaining rivet that was improperly formed on 2021 and 2022 trucks. Separately, recall 20V735 covers front seats whose attachment bolts may not have been reinstalled after an assembly-line repair, so an occupied seat could move in a crash. All four are free inspections and replacements. GM also ran a satisfaction programme on the driver's inboard seat-mounted airbag connector, where "driver movement can disrupt the electrical connection," showing a Service Restraints System message before the airbag would fail to deploy.

DFM — Dynamic Fuel Management, the successor to AFM that can shut down any combination of the eight cylinders — uses the same collapsible-lifter idea and fails the same way. The 6.2L recall does not cover the 5.3L, and this year's file has 5.3L failures in it: "My 2021 GMC Yukon AT4 with a 5.3L engine failed as I was driving down a highway going to my child's ballgame. It put me at risk of wrecking on the highway with other traffic around me." Another owner describes the mechanism from the driver's seat before anything broke — the truck "hesitated and bucked while accelerating and switching between 4- and 8-cylinders operation." There is no recall and no special coverage for the 5.3L on this model year. Cold-start it, listen for a tick, and take any hesitation on cylinder transitions seriously.

The new independent rear suspension rides far better, but the air-levelling option had a rough launch and GM's own bulletins say so. One 2021 bulletin describes a Service Levelling or Service Headlight message with code U0132, "Lost Communication with K5 Automatic Level Control Module," and no communication available with the module at all — closing with the words "Engineering is working on a fix." A companion bulletin records a parts restriction on that same module, requiring dealers to call GM to order one. Later bulletins cover a pinched air inlet hose to the compressor setting code C1197, and air lines that were not fully seated. Two hands-on teardowns give the wear pattern that costs the most: a leaking air spring makes the compressor run constantly until it burns out, so you replace both. Park it overnight and check for settling; listen to the compressor on start-up.

Two more items with documents behind them. Recall 22V036 covers rear driveshaft assemblies with "internal components that were not heat-treated properly, possibly resulting in driveshaft failure" and a sudden loss of drive power; dealers replace the left and right rear driveshafts free. Separately, GM's Special Coverage for the engine coolant control valve covers 2021 through 2023 trucks where the valve fails an on-board diagnostic test, lighting the check-engine lamp and setting a code, and where "in some cases, the engine cooling fans may run after the engine is switched off" — replaced at no charge. If you hear fans running after you have locked the truck and walked away, that is the symptom, and it is somebody else's bill.

The new diesel arrives with its own coverage and its own campaign. GM's Special Coverage for a cylinder-2 glow-plug failure runs fifteen years or 150,000 miles from first service, regardless of ownership. Recall 24V797 covers the diesel transmission control valve, which can fail and lock the rear wheels, with new control-module software installed free and a special coverage programme for transmissions the software identifies as defective. Note that a later campaign, 25V619, covers 2021 Tahoe and Escalade diesels whose fuel tank may have been replaced with an incorrect tank that can leak in a rollover — it names the 2022 and 2024 Yukon rather than the 2021, so it does not apply here, but it is worth knowing the diesel fleet has been through a tank campaign. If you are buying the diesel, confirm both the glow-plug coverage and 24V797 by VIN.