Hydraulic brake systems can develop leaks in the brake lines, master cylinder, or calipers, leading to reduced braking performance.

Heavy use or overheating can cause brake rotors to warp, leading to vibration or pulsation during braking.

Brake pads wear down over time and need regular inspection and replacement to maintain braking efficiency.

The Anti-lock Braking System (ABS) may malfunction, causing the ABS warning light to illuminate and affecting braking performance.

A failure in the vacuum pump can lead to reduced brake assistance, making it harder to press the brake pedal.

The L87 engine may experience higher-than-normal oil consumption, requiring more frequent oil top-offs and monitoring.

Some models with the L87 engine have reported issues with valve lifter failure, leading to engine noise and potential performance loss.

Direct Injection (DI) engines like the L87 can experience carbon buildup on intake valves, affecting engine performance and fuel economy.

V-shaped engines can have cooling inefficiencies, leading to potential overheating problems if not properly maintained.

Over time, the timing chain in the L87 engine can wear out, leading to noise and potential engine timing issues.

Hydraulic brake systems can develop fluid leaks, which can result in reduced braking efficiency.

Over time, brake pads can wear down and need to be replaced to maintain proper braking function.

Squeaking or grinding noises can indicate worn brake pads or rotors.

A spongy or soft brake pedal can signify air in the brake lines or a problem with the master cylinder.

The V-shaped engine configuration might consume more oil, leading to the need for more frequent oil changes.

The complexity of a V-shaped engine can sometimes lead to overheating issues if not properly maintained.

The L87 engine may experience misfiring due to issues with spark plugs, ignition coils, or fuel injectors.

Over time, the timing chain in the L87 engine can wear out, leading to poor engine performance or failure.

Direct Injection (DI) engines can suffer from clogged or faulty fuel injectors, affecting performance.

The Dynamic Fuel Management system can develop faults, leading to inconsistent engine performance.

Problems with the cylinder deactivation system can lead to rough idling or performance issues.

The aluminum engine block can wear over time, particularly if not properly maintained.

V-shaped engines often have more complex cooling systems, which can be prone to leaks.

The GMC Sierra may experience transmission problems, such as rough shifting or slipping gears, which can affect overall performance.

Modern vehicles, including the 2021 GMC Sierra, can suffer from various electrical issues, such as faulty sensors or wiring problems.

Hydraulic brake systems rely on brake fluid to transfer force from the brake pedal to the brake components. Leaks can lead to reduced braking efficiency and potential brake failure.

Extended usage, especially under heavy load or during downhill driving, can cause the brake system to overheat, leading to reduced braking power.

A spongy or soft brake pedal can indicate air in the brake lines or issues with the master cylinder.

The anti-lock braking system (ABS) can experience sensor failures or electrical issues, leading to diminished effectiveness in preventing wheel lockup.

Over time, brake rotors can warp due to excessive heat, causing vibrations or pulsations when braking.

Brake pads wear out over time and need regular replacement to ensure effective braking performance.

The V-shaped, 8-cylinder L87 engine may experience misfires due to issues with ignition coils, spark plugs, or fuel injectors.

Some users report higher-than-expected oil consumption in the L87 engine, necessitating frequent oil level checks and top-offs.

The L87 engine might encounter problems with the timing chain, including stretching or premature wear, which can affect engine timing and performance.

Issues with the direct fuel injection system can lead to poor fuel economy, rough idling, or difficulty starting the engine.

Overheating problems due to radiator, water pump, or thermostat failures can cause significant engine damage if not addressed promptly.

The GMC Sierra is known to have issues with its transmission, including hard shifts, slipping, or delayed engagement.

Hydraulic brake systems can develop fluid leaks, which can result in reduced braking efficiency.

Over time, brake pads can wear down and need to be replaced to maintain proper braking function.

Squeaking or grinding noises can indicate worn brake pads or rotors.

A spongy or soft brake pedal can signify air in the brake lines or a problem with the master cylinder.

The V-shaped engine configuration might consume more oil, leading to the need for more frequent oil changes.

The complexity of a V-shaped engine can sometimes lead to overheating issues if not properly maintained.

The L87 engine may experience misfiring due to issues with spark plugs, ignition coils, or fuel injectors.

Over time, the timing chain in the L87 engine can wear out, leading to poor engine performance or failure.

Direct Injection (DI) engines can suffer from clogged or faulty fuel injectors, affecting performance.

The Dynamic Fuel Management system can develop faults, leading to inconsistent engine performance.

Problems with the cylinder deactivation system can lead to rough idling or performance issues.

The aluminum engine block can wear over time, particularly if not properly maintained.

V-shaped engines often have more complex cooling systems, which can be prone to leaks.

The GMC Sierra may experience transmission problems, such as rough shifting or slipping gears, which can affect overall performance.

Modern vehicles, including the 2021 GMC Sierra, can suffer from various electrical issues, such as faulty sensors or wiring problems.