California Lemon Law Attorneys

2018 GMC Sierra Problems: Info for California Drivers

  • By: Jessica Anvar
  • May 23, 2022
2018 GMC Sierra Problems: Info for California Drivers

The 2018 GMC Sierra is a full-size truck that drivers rely on for their commutes and their livelihoods. GMC boasts that the Sierra has top-notch towing capabilities and a comfortable interior.

However, customers have been displeased because of the 2018 GMC Sierra problems with the transmission and engine problems. Plus, the 2018 Sierra’s three recalls due to defective brakes may not inspire confidence in Sierra owners.

2018 GMC Sierra Transmission Problems

Drivers rely on the smooth shifting of gears in the transmission to accelerate. However, customers have reported numerous problems with the 2018 GMC Sierra transmission, such as hard shifting and banging.

One driver reported his 2018 GMC Sierra 1500 problems to Edmunds:

The 8spd trans clunks, bangs 2nd to 3rd to 4th. Under throttle I hear no issues, city driving idling along, say 10-15mph, roll on and off the throttle and there are serious bangs going on, up and down. It reminds me of an old drive line ready to spit u joints at any time, it’s not in the rear end (ring n pinion lash), seems to be in the tranny. I have parked the truck, sits for +/-2hrs, level, on start up the rear tires jerk the truck hard, [definately] gets your attention. Does this about once every 10-15 start ups. Took to the dealer and of course they say there is nothing wrong.

Complaints about the 2018 GMC Sierra transmission problems are common. GMC is aware that drivers may experience banging and clunking when the 2018 Sierra shifts.

GMC issued Service Bulletin No.: 16-NA-019, which instructs mechanics on how to repair hard shifts, splits, and flares when a customer brings their vehicle to the shop. However, according to the customers above, GMC has done little to help their customers and has refused to cover these issues even where vehicles are under warranty.

2018 GMC Sierra Engine Problems

The engine is clearly a critical component of any vehicle. However, customers have complained about the 2018 GMC Sierra’s 6.2 engine problems. In particular, drivers routinely deal with defective radiators, broken lifters, and problematic starters, among other problems.

One owner reported to the National Highway Traffic Safety Administration (NHTSA):

I have had my GMC Sierra 1500 for almost 3 years. I have a little under 59,000 miles on the truck. A few thousand miles ago a tech at the gm dealer let me know that they had to add some coolant and it was something I should keep an eye on. I brought the vehicle back to have them look into it. They let me know that the radiator has a small leak. It is not big enough to have fluid hit the ground in my garage but it is losing fluid. I looked online and saw that this is a common issue. I was told that it was not covered under warranty and it would cost a good amount to fix. I have had this vehicle for under 3 years and have had 5 issues without any of them being covered by warranty. This vehicle seems to be a lemon.

The 2018 Sierra has many additional engine problems. This driver reported their 2018 GMC Sierra Denali problems with the lifters to Edmunds:

All was good with the truck until 11k miles. 1.5 mi run to run errands and the engine tried to stall in the middle of traffic. 11k miles. Dealer towed it in and found the AFM special lifters failed and all had to be replaced. A KNOWN issue on GMC engines with AFM.

Customers wouldn’t be as concerned if these were the only complaints about the 2018 Sierra’s engine. However, there are numerous complaints on the forums about engine problems, such as the 2018 GMC Sierra starter problems, problems with the radiator, and broken lifters.

Although GMC has issued service bulletins to diagnose lifter issues (Service Bulletin No.: 15-06-01-002H), starter problems (Service Bulletin No.: 18-NA-161), and radiator leaks (Service Bulletin No.: PI1513F), customers have spent a great deal of money to repair these problems.

California Lemon Law Rights For Your 2018 GMC Sierra Problems

You may feel dismayed like the customers above who spent significant amounts to repair the numerous 2018 GMC Sierra problems, despite their vehicles often being under warranty. You may have rights under California’s expansive Lemon Law.

Under California law, if you have a warrantied vehicle that has experienced significant problems, a manufacturer must repair, replace, or repurchase your vehicle. They also are responsible for paying your attorney fees.

The manufacturer can also be liable for additional damages if they willfully fail to follow the Lemon Law. Don’t rely on manufacturers to do the right thing while your truck waits for repairs in the shop. Contact a lemon law attorney for help.

Contact the Lemon Law Experts for Your 2018 GMC Sierra Issues

You do not have to handle the manufacturer or lemon law claim alone. The Lemon Law Experts have experienced attorneys who’ve fought the major automobile manufacturers to ensure that our clients receive what they deserve under California’s Lemon Law.

Call us or contact us online today so that you don’t have to face this battle on your own.

Jessica Anvar
About Jessica Anvar

Jessica Anvar

Jessica Anvar is the Founder and Managing Partner of the Lemon Law Experts, a California consumer lemon law firm she founded in 2009. Jessica is a California-licensed attorney with many years of legal experience, focusing her practice on representing consumers in Lemon Law and automotive warranty disputes. She has extensive experience handling claims against major auto manufacturers and advocating for consumers seeking vehicle repurchases, replacements, and monetary compensation under the California Lemon Law. Jessica earned her law degree from Loyola Law School and her Master of Business Administration from Loyola Marymount University in Los Angeles. She has dedicated her legal career to protecting consumer rights and is also licensed to practice law in Texas, Ohio, Colorado, and Washington.

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