Best and worst GMC Sierra years — which to avoid

Ever since its debut in 1988, the GMC Sierra is considered to be one of the most reliable pickup trucks on the market, but even as such it had a few unimpressive model years. Buying one requires a careful scanning of the market and getting to know the best picks reliability-wise, as well as the worst GMC Sierra years to avoid.

Since it’s not always that easy, our team will ensure that you get all the necessary pieces of information on the best and worst GMC Sierra years. Through model-specific concerns, driver reviews and ratings and official NHTSA recalls and complaints, we’ll present to you the best possible options to buy, as well as flawed versions to avoid.

Why you can trust REREV’s advice on which car model years to avoid: Our car experts look at official data, ask real drivers what they think, and talk to experienced mechanics to make sure our list is useful. This reliable info can make buying a car easier for you. Want to know how we do it? Find out more about our research methodology.

How we rated the best and worst GMC Sierra years

As we went through the Sierra model years, we wanted to only use verified information when evaluating the best and worst model years. We know how important it is to you to be able to trust a buying guide, and that’s why we mostly used trustworthy information from NHTSA and the Insurance Institute for Highway Safety.

This way, our expert team members managed to obtain data on common driver complaints, official recall logs, and safety ratings to see what went wrong with Sierra years you should avoid. We also did some exploration of first-hand driving experiences through Sierra forums and platforms like Consumer Reports, KBB, and Edmunds, so here’s our final list:

Most common GMC Sierra problems

Over the years, GMC Sierra didn’t show any signs of serious mechanical faults or problems, but there were some minor issues with specific model years.

One of the most expressed issues for the Sierra models includes electric system problems and bad connections including wiring harnesses. While the electrical features caused a lot of trouble for owners with accessories and features, it wasn’t as crucial as the engine problems.

1. Transfer case problems

One of the most annoying problems was a bad transfer case which caused problems with the all-wheel-drive system.. It’s a crucial part of the drivetrain for an all-wheel-drive pickup like Sierra since it transfers the torque from the transmission to the drive axles.

So, if the transfer case goes out, drivers may face problems with the AWD system and it may be especially inconvenient in situations where the added thrust is needed. Sierra is an off-road capable pickup, so we can imagine how much trouble you’d get if the transfer case can’t do its purpose and leaves you stuck in the mud. This issue was most persistent for the 2007 and 2012 models.

2. Electric system faults

Another standout flaw of the Sierra is in the car’s electric system since numerous problems affected by it occurred to drivers. Some of the most prominent ones included excessive battery discharge issues, A/C system faults, and even taillights and blinker malfunctions.

However, one of the most dangerous issues was the complete ECU fault, and the engine control unit controls the combustion process. So, if this vital component fails due to electrical issues, it endangers the engine and may result in an imprecise combustion mix. We know. it’s a lot to process, but the good thing is – these problems have only been reported for a few model years.

3. Problems with the V6 engine

As mentioned, the 4.3-liter V6 engine is one of the worst options for a Sierra, and it was on offer for three generations. The engine was later on revised for the fifth generation, so it doesn’t cause as many problems, but it’s still less reliable than a 5.3-liter or a 6.2-liter V8.

There were several issues reported for the Sierra cars equipped with this engine, especially for the 2005 and 2007 Sierra. Namely, some of the major faults included carbon buildups that prevented proper airflow into the engine and fuel delivery system faults.

However, this engine also had a system called the active fuel management system, and it turned out to be a bad option. While it should have deactivated two cylinders to improve fuel efficiency, it turned out to be a bad thing and additional stress put on the engine, especially in the 2005 to 2007 period.

4. Dashboard gauge failures

Finally, there’s the issue with a speedometer not working and the fuel gauge getting stuck, and not reading the fuel level accurately. While fuel gauge issues are pretty common for GM vehicles, the speedometer issue turned out to be dangerous while driving.

It also reduced the driver’s attention on the road and required the use of GPS speedometers to determine the driving speed, so it’s just one big mess.

Worst GMC Sierra years to avoid

When it comes to summing up the general problems that drivers had with the Sierra in all generations, there aren’t that many problems. We only have several model years to blame for bringing partial disgrace to the reputation of this otherwise reliable pickup.

So, that begs the question – what are the worst GMC Sierra years to avoid? The worst GMC Sierra years are by far 2005 and 2007, but here’s a complete overview of all the years you should avoid:

• 2005
• 2006
• 2007
• 2012
• 2014
• 2015
• 2019

Let’s now take a closer look at these and their problems to see what exactly made them bad options for drivers.

Second-generation GMC Sierra (2005-2006 model years)

The final two years of production for the second-gen Sierra turned out to be the worst for the whole generation. They faced a lot of electrical issues, as well as problems with the initial 4.3-liter V6 before the revised EcoTec 3 version.

On top of that, there’s the failing speedometer problem that was the most expressed for these two model years, making them not so desirable for drivers.

Third-generation GMC Sierra (2007 and 2012 model years)

The 2007 and 2012 model years are some of the worst for the GMC Sierra due to their electric issues and transfer case problems. Some of the dashboard gauge failures kept going on with this generation and it’s also a bad thing that drivers experienced poor-quality interior materials.

That’s why these two model years may not bring you the best bang for your buck while looking for the most reliable Sierra model year.

Fourth-generation GMC Sierra (2014-2015 model years)

2014 is one of the worst years of production for the Sierra since it comes with several major issues. One of the main problems is the issue with electrical features. These were affected by the troubles that previous model years had, but GM only made them worse instead of fixing them.

That’s why you may experience seizing headlights, seat heaters, and the A/C system along with the entire infotainment system control pillar. Drivers also reported hearing strange transmission noises and harsh gear shifts for these model years. On top of that, there were some problems with the peeling paint and rust that quickly formed on the exterior, making it arguably the worst Sierra ever made.

Fifth-generation GMC Sierra (2019 model years)

Finally, we have the 2019 Sierra which ended up receiving a lot of driver criticism due to faulty ECU and problems with harsh automatic transmission shifting. Also, there were some problems with the airbag system and seat belts that were not properly tightened, creating a safety concern.

What are the best GMC Sierra years to buy?

The GMC Sierra makes a wonderful ride among affordable pickup trucks on the US market and it’s both comfy and spacious, along with the off-road potential it comes with. We already explained the worst model years and their problems, so it’s finally time to focus on the good stuff:

• 1995
• 1996
• 1997
• 1998
• 1999
• 2000
• 2001
• 2002
• 2003
• 2004
• 2008
• 2009
• 2010
• 2011
• 2013
• 2016
• 2017
• 2018
• 2020
• 2021
• 2022

As you can see, Sierra makes a reliable ride overall, and the best piece of advice you can get is to avoid troublesome models like the 2005, 2007, 2012, and 2019 Sierra. By doing this and avoiding the 4.3-liter V6 in earlier generations, you can make sure that the Sierra you buy will last for quite some time.

Some of the most reliable Sierra model years include the 2009 and 2020 Sierra, so we’ll further discuss those models.

2009 GMC Sierra

The 2009 GMC Sierra has the lowest rate of complaints submitted to NHTSA and that makes it a perfect choice for those looking for a reliable third-gen model. It also brought a lot of positive feedback from drivers and previous owners both in terms of engine reliability and other mechanical features.

It only had a few issues with the braking system and the electrical features but it more or less made it one of the most reliable Sierra models so far and it didn’t have any major faults.

2020 GMC Sierra

Just as the 2009 model, the 2020 Sierra was pretty much without any serious issues, although it faced some minor complaints for which GMC issued official recalls. Among those, we can mostly point out the issues with the braking system, electrical faults, and airbag problems.

Even so, this model received by far the least complaints among the latest fifth-gen options, and drivers especially praised its ruggedness and stability on the road.

Is the GMC Sierra worth buying?

The final answer is – yes, GMC Sierra is worth buying based on everything we’ve covered in this guide. While there are some problematic model years, there were many more impeccable production years. Sierra manages to cope and even beat the competition like Nissan Titan and Toyota Tundra in terms of reliability that’s on par with the F-150.

So, as long as you use our guide to steer away from the problematic model years, you’ll get at least 250,000 miles out of your pickup, and possibly even more.

Considering a new pickup? Our insights on the Ford Ranger years to avoid, Dodge Dakota years to avoid, and Chevy Avalanche years to avoid detail the years to target and ones you would want to skip.