2020 CHEVROLET SILVERADO 3500 Power Train Problems

On [XXX], while driving ~65 mph, my 2020 Chevrolet Silverado 2500HD Duramax experienced a sudden transmission lock-up, nearly causing a crash. The event caused severe internal transmission damage, leaving the truck unsafe and inoperable. This is the exact defect described in NHTSA Recall #24V-797 (GM Recall N242454440), which states that valve body wear can cause rear-wheel lock-up. My truck stored P0700 and P2820, which directly indicate a valve body failure. GM refuses to repair my vehicle under Special Coverage N242454441 (15 years/150,000 miles) because code P0747 did not set, even though my failure clearly matches the defect. I requested a hydraulic valve body leak test, the only way to confirm the defect, but the dealer refused, saying they only scan codes. GM must perform this test at no cost, as required by federal recall laws. GM’s denial leaves a known safety defect unrepaired, violating federal recall obligations and putting drivers at risk. NHTSA action is needed to require GM to repair vehicles like mine, regardless of which DTC is stored. VIN: XXX Mileage at failure: 145,560 Dealer: Ken Garff Chevrolet – American Fork, Utah GM Case #: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2020 Chevrolet Silverado 3500. The contact stated that the check engine warning light was illuminated. Additionally, the vehicle later failed to start and became undrivable. The dealer was notified of the failure and an appointment was scheduled for diagnostic testing and for the manufacturer internal recall repairs. The vehicle was not diagnosed or repaired. Additionally, the contact became aware that the VIN was included in NHTSA Campaign Number: 24V797000 (Power Train); however, the local dealer was contacted and informed the contact that the dealer was not aware of the recall. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue via email, but no assistance was provided. The failure mileage was approximately 28,000. Parts distribution disconnect.

Mileage: 28,000

The contact owns a 2020 Chevrolet Silverado 3500. The contact stated while driving 65 MPH, the rear wheels locked-up. The contact was able to pull over to the side of the road. The contact resumed driving, but the vehicle was driving roughly, and the failure recurred while driving 30 MPH. The check engine warning light, the electronic stability control warning light, and other unknown warning lights were illuminated intermittently. The contact pulled into a gas station, where a mechanic inspected the vehicle, but the cause of the failure could not be determined. The vehicle was towed to the dealer, where it was diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was not repaired due to the cost. The contact related the failure to NHTSA Campaign Number: 24V797000 (Power Train); however, the VIN was not included in the recall. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was unknown.

I recieved a recall notice from Chevrolet stating they needed to install a software update to the truck which will warn if a potential rear wheel lock up is about to occur due to faulty transmission valve body- which was stated that they do not have a fix for. After software update was installed- I was driving about 35 mile per hour on the trip home, and the truck abruptly downshifted very hard, momentarily locking up rear wheels, and the check engine light came on, and the vehicle message came up stating the vehicle was placed in a reduced propulsion mode(limp mode). The next day it did it again on my short drive to work of 2 miles. I took into dealership and they informed me that the valve body had failed- as mentioned in the recall notice. It is now 1 month later and I still do not have my truck back, the part is back ordered, and they have no idea when it will be fixed. I am without my primary form of transportation.

The sudden rear wheel lock up recall that GM has released for the 2020+ Silverado's with the 10-speed transmission does not go far enough. The recall simply reprograms the PCM to alert the driver 10,000 miles prior to the valve in the valve body failing, puts the vehicle into limp mode, and extended the warranty on the valve body to 15 years or 150,000 miles. GM states there is no fix available and this is not correct. NextGen Drivetrain has developed a fix for this per their website [XXX] ). On their site they also provide videos of trucks experiencing the lock up where it seems that the vehicle downshifts to 2-nd gear at high speeds and creates a violent jolt. This is extremely troubling to me as these vehicles are meant to tow, and I am very fearful that this issue will happen while towing a long trailer while my family and I are traveling and putting them in danger of an accident. It is very concerning to me that NHTSA would allow for this type of a "FIX". I am not sure if you have seen the videos of this issue happening, or know that a fix does seem to have been developed. I ask that you please reopen this investigation and revisit the way GM is handling this recall, and look into the fix that NextGen drivetrain has developed. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2020 Chevrolet Silverado 3500. The contact stated that while driving on [XXX] at 70-73 MPH, the vehicle unexpectedly downshifted to first gear. The contact slammed on the brake pedal and pulled over to the side of the road. The vehicle was turned off. The contact stated that the tachometer had increased to over 3,000 RPM. The vehicle then red-lined. There were no warning lights illuminated. The vehicle was taken to the local dealer, where it was diagnosed that the valve body control needed to be replaced but was on backorder for a month. The vehicle was repaired, but the vehicle failed to recognize the part. The dealer informed the contact that the transmission needed to be replaced. The vehicle was repaired, but the failure recurred. While driving, there was an abnormal knocking sound coming from the vehicle. The contact was able to pull over safely. The vehicle was towed to another local dealer, Spitzer Chevrolet Amherst (200 N Leavitt Rd, Amherst, OH 44001), where it was diagnosed and determined that the engine needed to be replaced. The contact was informed that the torque converter was wobbling, and the crankshaft bearings were shot. The vehicle was not repaired. The vehicle was towed to an independent mechanic who determined that the oil filter had metal shavings inside. They removed the oil pan and noticed the crankshaft had broken in half. The vehicle was not repaired. The contact received notification of NHTSA Campaign Number: 24V797000 (Power Train); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 178,000. Parts distribution disconnect. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Mileage: 178,000

The contact owns a 2020 Chevrolet Silverado 3500. The contact received a notification of NHTSA Campaign Number: 24V797000 (Power Train) however, the part to do the recall repair was not yet available. The contact stated that while driving at 62 MPH during snow weather and switching lanes; the accelerator pedal was depressed, and both the rear wheels had locked. The vehicle spun out of control and traveled into the center lane of a two-lane road and crashed into a snow embankment where it came to a stop. No Injuries were sustained. No warning light illuminated. Prior to the crash, the contact stated that the transmission was slipping and making abnormal noises where it was taken to a dealer for the transmission was inspected and replaced due to metal shaving intrusion. The vehicle was then taken to the same local dealer for the most recent failure where it was diagnosed with a transmission failure related to the open recall. The vehicle was towed back to the residence where it was informed that the recall remedy was not available and no interim repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The failure mileage was approximately 40,000. The contact mentioned that the failure mileage for the most recent failure was 28,000 with the new transmission. The manufacturer was made aware of the failure and confirmed that there was no recall remedy available and no expected available date determined. VIN tool confirms parts not available.

Mileage: 40,000

Dealership told me the throttle body failed in my transmission. I wanted it completely torn down to find the actual point of failure since it did represent the current recall on the truck that hadn't been done because the part isn't yet available. The transmission has been replaced for almost $10,000.00

2nd time I’ve had to replace def heater and tank. Truck goes into limp mode and limits the speed leaving a person stranded.

Transmission lock up traveling 45 miles an hour while acceleration up modest uphill grade pulling a 3000 pound trailer. The lockup was severe enough to cause passengers to lunge forward with seatbelt engagement. There was no loss of control of the vehicle; however, we did stop the vehicle to inspect it with no damage observed. We expected to see some. This event would have caused a likely loss of control of the vehicle if the lockup was for longer duration. Vehicle also had prior hard shifts that are still occurring. These hard shifts usually occur in the lower gears with acceleration and deceleration. Vehicle was taken to the dealership with an explanation of the event. There were no codes. The dealer recommended a transmission fluid change to smooth the shifting. This seemed to decrease the frequency of the hard shifts but did not eliminate them. The vehicle has not been inspected by police, manufacture or insurance company. The dealer did not do a thorough transmission inspection. I suspect they knew of this problem at the time of the transmission fluid change due to the current recall: Manufacturer Recall NumberN242454440 NHTSA Recall Number24V797