2026 Chevrolet Tahoe Problems

While driving the vehicle at highway speeds the vehicle starts to lurch or randomly lose power. Eventually, within a few minutes, the lurching gets worse and the check engine light starts flashing. In a GM vehicle, a flashing check engine light is critical engine failure. After pulling the vehicle to the side of the road, the check engine light stops flashing and stays on constantly. After about 10-15 minutes, the check engine light turns off completely. The GM dealership can read the history and says it's P0300 error code for General Engine Misfire in cylinder #6. GM warranty refuses to fix anything because the light isn't on when the car comes into the dealership. The car has been to two different dealerships, with both of them telling me it has the same error code. GM customer service told me without the check engine light being on when the vehicle is brought into the dealership, they would not be able to help me. This is being told to me even though everyone agrees that the check engine light has been on. I was told by GM to continue to drive the vehicle. It has been into the shop 4 times since January for the same issue. This is not safe as the engine has suffered a critical issue. I don't feel safe driving the vehicle. My GM Customer Service case is 110460594.

At approximately 4,200 miles, the engine on my 2026 Chevrolet Tahoe High Country equipped with the 6.2L V8 suddenly shut off while the vehicle was stopped at a traffic light. There were no warning lights, messages, unusual noises, or other symptoms prior to the failure. The vehicle would not restart and had to be towed to an authorized Chevrolet dealership. The dealership initially suspected a camshaft/lifter or related engine issue and performed diagnostic and mechanical testing. The dealer also opened a case with General Motors. GM subsequently directed the dealership to perform an ECM software update. After the update, the engine started and the vehicle appeared to operate normally. As part of the dealer's post-repair testing, a dealership employee drove the vehicle to confirm the issue was resolved. After approximately 7–10 miles, the vehicle suffered another engine failure while being driven and again became inoperable. The problem was therefore reproduced and confirmed by the Chevrolet dealership. Following the second failure, GM authorized replacement of the complete engine. The dealership has received a brand-new replacement engine and is replacing the engine and radiator. The original engine/component is currently at the dealership and may be available for inspection. I consider this a serious safety concern because the engine failed without warning while the vehicle was in use. Had the initial failure occurred while traveling at highway speed or in heavy traffic rather than while stopped at a traffic light, the sudden loss of engine power could have created a significant risk of a collision. The vehicle is a 2026 model with approximately 4,200 miles. I am reporting this because of the extremely low mileage at which the engine failed, the absence of any warning before the failure, and the fact that the vehicle failed a second time shortly after GM's initial attempted remedy.

I was on the interstate. Initially I heard a faint rattling sound. I turned off the radio and AC to listen more closely; the sound was not audible. But then traffic came to a standstill. As I slowed, that barely audible noise began to sound like something boiling in the engine. The temperature and pressure gages were all in normal operating ranges. I pulled to the shoulder of the interstate and checked under the hood. I noticed a distinctive squeaking sound although the fan belt was intacted in running true. There was no sign of any fluid loss in the engine compartment or underneath the vehicle. While attempting to get to a Chevrolet Dealership one exit away, the vehicle stopped running while at a stop light. additionally, there is a recall on this vehicle for the automatic braking system. GM and the dealerships are aware of this recall yet this website states there are no recalls.

Control algorithm issue. Unexpected acceleration. Not confirmed by dealer. I experienced it twice. Google Gemini sems to know about this. No inspections performed. No warnings. There is a safety issue with the 2026 Chevrolet Tahoe adaptive cruise control. My observation: On a previous drive, I used the adaptive cruise control with it set at highway speed. I disengaged it as I got off the highway using the brake pedal and arrived at my destination via city streets. I turned the vehicle off, exited and locked it. Later, I re-entered the vehicle, started it and began slow speed maneuvering (<5mph) in my driveway, where in, I accidentally bumped the cruise control “Resume” switch, at which time the vehicle began to accelerate, unexpectedly. I stepped on the brake to regain control. No accident occurred. This happened a second time upon my return from the local supermarket. In my opinion, the cruise control should return to the OFF mode when the engine is turned off and not remain “On” and ready to “Resume” after the engine has been cycled. The current operating mode is unsafe.

While driving the vehicle at highway speeds the vehicle starts to lurch or randomly lose power. Eventually, within a few minutes, the lurching gets worse and the check engine light starts flashing. In a GM vehicle, a flashing check engine light is critical engine failure. After pulling the vehicle to the side of the road, the check engine light stops flashing and stays on constantly. After about 10-15 minutes, the check engine light turns off completely. The GM dealership can read the history and says it's P0300 error code for General Engine Misfire in cylinder #6. GM warranty refuses to fix anything because the light isn't on when the car comes into the dealership. The car has been to two different dealerships, with both of them telling me it has the same error code. GM customer service told me without the check engine light being on when the vehicle is brought into the dealership, they would not be able to help me. This is being told to me even though everyone agrees that the check engine light has been on. I was told by GM to continue to drive the vehicle. It has been into the shop 4 times since January for the same issue. This is not safe as the engine has suffered a critical issue. I don't feel safe driving the vehicle. My GM Customer Service case is 110460594.

Driving on the Highway the Engine failed at highway speeds and the Tahoe experienced a complete shutdown, we could not restart the vehicle nor shift to neutral. We had the vehicle towed and was told by the dealer that it needs a engine replacement at 14,000 miles.

Service break assist light came on 2 days after getting the brand new vehicle. They ended up needing to replace the break Master cylinder

The contact owns a 2026 Chevrolet Tahoe. The contact stated that two hours after parking the vehicle in the garage and turning off the vehicle, there was excessive heat coming from the vehicle, and the vehicle was extremely hot to the touch above the wheel well. Due to the heat coming from the vehicle, the contact stated that it was difficult to breathe while inside the garage. The vehicle was taken to the local dealer, but no failure was found with the vehicle. Later, while driving the vehicle, the vehicle lost power, and the check engine warning light was illuminated. The vehicle was driven back to the nearby dealer and was diagnosed with a fuel pump module and fuel pump hose failure. The contact was informed that the parts needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure. The failure mileage was 129.

See attached document for complaint.