The GMC Sierra 1500 is a capable and well-appointed full-size pickup, but it shares its platform, engines, and transmissions with the Chevrolet Silverado. This means that, for all its benefits, it can share many of the same engine and transmission concerns found in comparable Silverado models.

Across recent Sierra 1500 generations, owners have reported issues involving cylinder-deactivation hardware, engines, and automatic transmissions, although the specific problems vary by model year and powertrain. By knowing which model years may be vulnerable, you can plan ahead if you’re shopping or be in the know with a truck you already own.

K2XX Generation (2014-2018): The AFM Lifter Problem

The K2XX generation of Sierra 1500s arrived with GM’s EcoTec3 V8 engines featuring Active Fuel Management (AFM), a cylinder-deactivation system that has been associated with documented lifter problems on certain vehicles. AFM works by shutting down four of the eight cylinders when under light load in order to save fuel. The special hydraulic lifters used by the system can develop problems, including lifters that become stuck or collapse, potentially resulting in misfires, ticking or tapping noises, and rough engine operation.

When a lifter collapses, it can damage the corresponding camshaft lobe, turning what may have been a parts-only fix into something much more. Lifter repairs can become labor-intensive, particularly if a failed lifter damages the camshaft and additional valvetrain components require replacement. Actual repair costs vary based on the extent of the damage, engine configuration, labor rates, and repair facility.

Because the 2014 and 2015 Sierra trucks are now more than a decade old, shoppers should pay particular attention to engine condition, maintenance history, abnormal valvetrain noise, misfire codes, and evidence of previous lifter or camshaft repairs.

T1XX Generation (2019-Present): DFM and Transmission Concerns

The Sierra was redesigned for the 2019 model year on the T1XX platform, with certain V8 powertrains introducing GM’s more advanced Dynamic Fuel Management (DFM) cylinder-deactivation system. Unlike AFM, which primarily alternated between eight- and four-cylinder operation, DFM can use multiple cylinder-deactivation patterns based on driving conditions.

The T1XX generation also uses several automatic transmission configurations, including GM’s 10-speed automatic on certain powertrains. Owners have reported transmission concerns such as harsh or delayed shifting, and GM has issued service guidance and recalls addressing specific transmission conditions on certain vehicles. Because transmission type varies by model year and powertrain, shoppers should identify the transmission in a specific truck and review its service history, applicable technical service bulletins, and recall status.

Certain Sierra 1500 models have also been involved in GM recalls addressing transmission control-valve wear that could, under certain conditions, cause the rear wheels to lock. Buyers should check the truck’s VIN through NHTSA or GM to determine whether any applicable recall repairs remain outstanding.

Other Common Failures Across Generations

The above aren’t the only common issues seen in full-size truck models from GM. Beyond the engine and transmission issues, Sierra 1500 owners across both the K2XX and T1XX generations frequently report three additional failures:

1. A/C condenser leaks: A/C condenser leaks are one potential repair on Sierra 1500 models. Condenser replacement costs are approximately $730-$930.
2. Electrical and infotainment issues: Electrical problems can also involve components such as the Body Control Module (BCM), infotainment system, or trailer wiring. BCM replacement can be between $680-$750.
3. Brake rotor warping: Brake components are another potential ownership expense, particularly on trucks regularly used for towing or hauling. Brake rotor replacement costs approximately $570-$700.

Sierra 1500 Model Years to Research

For shoppers researching a used Sierra 1500, the following model years warrant additional attention:

• 2014-2015 Sierra 1500: GM service documentation specifically addresses AFM lifter concerns on certain 2014-2015 Sierra models equipped with the 5.3L L83 or 6.2L L86 engine. Because these trucks are also now more than a decade old, shoppers should pay close attention to maintenance history, abnormal valvetrain noise, misfire codes, and evidence of previous lifter or camshaft repairs.
• 2019 Sierra 1500: As the launch year of the T1XX generation, the 2019 Sierra introduced substantial changes to its powertrains, electronics, and other systems. Buyers considering one should carefully review its engine and transmission configuration, service history, recall status, and applicable GM service bulletins.

Sierra 1500 Model Years to Consider

Later K2XX models, such as the 2017 and 2018 Sierra 1500, may appeal to buyers looking for newer examples of that generation, but engine configuration, mileage, maintenance history, and overall condition remain important considerations. A well-maintained 2017 or 2018 model with complete service records and a satisfactory pre-purchase inspection may be worth considering.

Newer model years aren’t automatically more reliable. Buyers considering a T1XX Sierra should evaluate the specific engine and transmission combination, maintenance and repair history, recall status, mileage, and overall condition. A VIN-based recall check and pre-purchase inspection can provide more useful information than model year alone.

How an Extended Warranty Can Help With Ownership

Some Sierra 1500 repairs can be expensive, which may lead owners to consider additional vehicle protection. Depending on the specific vehicle and contract, a vehicle service contract may provide coverage for eligible components within systems such as the engine, transmission, air conditioning, and electrical system.

For Sierra owners approaching or beyond their factory warranty period, comparing potential repair costs with the price and coverage of an extended warranty or vehicle service contract can help determine whether additional protection fits their needs.

Endurance Warranty Services offers a variety of coverage plans for vehicles at all different mileage levels. Customers can generally take their vehicle to a licensed repair facility, including a dealership, for covered repairs. Endurance’s VIP Repair Network can also help customers locate certified repair facilities nationwide.

If you’re ready to protect your Sierra, contact an Endurance plan advisor at (800) 253-8203 or request a FREE quote. You can also quickly see your price and plan recommendations in our convenient online store.