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Lion Lemon

2020-2024 · Heavy Duty Pickup

GMC Sierra HD Lemon Law

Experiencing problems with your GMC Sierra HD? Our California lemon law attorneys can help you get the compensation you deserve.

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Common GMC Sierra HD Problems

The L5P 6.6L Duramax turbo-diesel engine suffers from fuel injector tip erosion and injector body cracking on cylinders 2 and 7, causing white exhaust smoke, rough idle, and fuel dilution of engine oil.
The Allison 10L1000 ten-speed automatic transmission develops a persistent whine in 9th and 10th gear under load, caused by worn final drive helical gear teeth and insufficient lubrication to the rear planetary gear set.
The diesel exhaust particulate filter (DPF) clogs prematurely due to incomplete regeneration cycles during short-trip driving, triggering reduced engine power mode and codes P2463 and P244B.
The integrated trailer brake controller module fails to apply proportional braking force, either over-braking or under-braking the trailer, caused by a defective internal accelerometer and corroded ground pin at connector X2.
The cab-to-frame mounting bushings deteriorate and crack, allowing excessive cab movement and producing loud popping and squeaking noises during trailer loading and when driving over uneven surfaces.

Your California Lemon Law Rights

Under California's Song-Beverly Consumer Warranty Act, if your GMC Sierra HD has a substantial defect that cannot be repaired after a reasonable number of attempts, you may be entitled to:

  • Full refund of the purchase price
  • Replacement vehicle of comparable value
  • Cash compensation (cash-and-keep settlement)
  • Attorney's fees paid by the manufacturer

GMC Sierra HD Lemon Law FAQ

Can I file a Lemon Law claim on my Sierra HD if the L5P Duramax engine has a known issue with a pending TSB?

Yes. The existence of a Technical Service Bulletin actually supports your lemon law claim because it demonstrates that GMC is aware of the defect. Under the Song-Beverly Act, you are entitled to a vehicle that conforms to the manufacturer's warranty regardless of whether a TSB has been issued. If the TSB repair does not resolve the issue, each subsequent attempt strengthens your case.

Does the Song-Beverly Act cover commercial-use Sierra HD trucks in California?

The Song-Beverly Act covers vehicles used primarily for personal, family, or household purposes. If your Sierra HD is used primarily for commercial purposes, it may fall outside the Act's protection. However, if the truck has a gross vehicle weight under 10,000 pounds and is also used for personal purposes, you may still qualify. Consulting with a lemon law attorney to evaluate your usage pattern is advisable.

My Sierra HD has been at the dealer for 45 days waiting for a transmission part. Does the wait time count toward my Lemon Law claim?

Yes. Under the Song-Beverly Act, every calendar day your Sierra HD is out of service for repair counts toward the 30-day threshold, including days the vehicle sits at the dealership waiting for back-ordered parts. The manufacturer cannot avoid liability simply because parts are unavailable. You should request written documentation from the dealer confirming the dates your vehicle was in their possession.

If my Sierra HD is a lemon, can I get a replacement truck instead of a refund?

Under the Song-Beverly Act, the consumer has the right to choose between a refund and a replacement vehicle. If you choose a replacement, GMC must provide a new vehicle that is substantially identical to your Sierra HD. The replacement must be of comparable value, and you should not have to pay any additional costs beyond the mileage offset deducted from the original vehicle.

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