Top 10 Least Reliable Cars, Trucks and SUVs of 2021

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2. Subaru Ascent

Subaru Ascent
Source: Car and Driver

While the Subaru Ascent proves to excel in short-term testing and road tests, it struggles long-term. CR surveyed Ascent owners and found some significant issues contributing to its low-reliability score.

Major trouble areas for the 2019 model were the transmission, climate system, brakes, power equipment and in-car electronics. The model apparently received some major improvements since then.

Now, the only trouble areas are in the transmission and power equipment categories. Regardless, continuous problems in major components could be trouble for long-term ownership.

1. Chevrolet Silverado/GMC Sierra 1500

Chevrolet Silverado
Source: Chevrolet

The 2021 GMC Sierra 1500 has all of the requirements to be a great full-size pickup truck. Along with a luxury interior, the Sierra has various engine options and impressive safety tech.

Despite its great assets, CR found that the GMC Sierra 1500 is one of the least reliable pickup trucks currently available. Similar to the 2021 Chevy Silverado covered in the same report, it struggles in critical areas. The worst being the brakes, power equipment and in-car electronics. Given the vehicle’s large size, having faulty brakes is not a good look.

Tech features in the Sierra don’t seem to be very reliable either. These sections cover the infotainment screen and vital components such as the instrument cluster, cameras and sensors.

Since the 2014 model, Sierra owners have consistently reported poor brakes. Although CR does not state exactly which brake issues plague the 2021 Sierra, the category covers components including the calipers, rotors and master cylinder.

On the bright side, the GMC’s previously reported issues found in the transmissions and drive system have supposedly subsided. And it seems that engine reliability has improved slightly since the 2020 model. While the scores are far from ideal, the Sierra seems to be on the right path.