The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving at an undisclosed speed, the vehicle intermittently shuddered. No warning lights was illuminated. The vehicle was taken to a dealer where it was diagnosed and determined that the torque converter needed to be replaced. The vehicle was repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 47,000.

- Spindale, NC, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving 30 MPH, the transmission became stuck in second gear. The contact pulled over the right side of the road and turned off the vehicle for two minutes. The vehicle was then restarted and there was an abnormal banging sound coming from the gear shifter. The vehicle was taken to the dealer where it was diagnosed and determined that the transmission needed to be replaced. The vehicle was not repaired. The Insurance Company had not yet been contacted. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was 141,000.

- Bayville, NJ, USA

I purchased a used 2018 Chevrolet Silverado High Country (VIN: [XXX] ) on [XXX], with 24,375 miles. On the day of pickup, the truck felt like it was driving over rumble strips. Dimmitt Chevrolet flushed the transmission and used the updated Mobil 1 HP LV fluid. This worked temporarily, but the shudder returned. CarMax then sent the truck to Burke-??s Transmission in Sarasota, where they replaced the torque converter. However, the shop declined to rebuild the transmission, citing its complexity. I later brought the truck to Cox Chevrolet in Bradenton. Despite clearly describing the shudder, harsh shifting, and driveline clunk, they told me the behavior was -??normal-?? and refused to investigate further, stating, -??We-??ll look into it once the unit fails completely.-?? The symptoms have worsened. Harsh 1-?"2, 2-?"3, and 3-?"4 shifts are back. Shifting into Drive causes a loud clunk and forward lurch. Cold starts cause bucking and sudden stopping. I-??ve replaced the tires, Bilstein 5100 rear shocks, and front suspension parts, but the problem persists. I signed on to a class action lawsuit against GM over the 8L90 transmission, but my claim was denied. This issue is well-documented and matches reports from many other owners. It affects drivability, safety, and long-term reliability. GM and its dealers have failed to properly address this known transmission defect. I urge NHTSA to investigate further. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Parrish, FL, USA

on or about [XXX] while driving through Olathe Kansas, the torque converter and subsequently the transmission on my 2018 Chevy Silverado 1500 failed while driving in heavy traffic. While navigating to a safe place outside the high-speed traffic corridor, the truck would run at approximately 3000 RPM at a speed of 40MPH. By sheer luck, we were not involved in a traffic accident. Replacement cost of the transmission unit was $7907.88 and $800 for a rental truck while the dealer replaced the transmission. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Princeton, MO, USA

transmission temprature excessively high, there is a TSB#21-NA-199 Document[XXX] on Thermo bypass vlave on 2018 trucks 6 speed transmissions. 200 degree transmission temp is too high. Service advisor originally said thats normal, after high temp issue a 5th time. I referenced the TSB #21-NA-199 to the dealership service advisor, Advisor said bring it in. Dealer replaced the original Thermo 198 degree transmission bypass valve with Gm's recommended 158 degree trans bypass vlave. Delaer proceeded to charged me $200 diagnostic fee and $167 for part and $258 for labor Total cost was $658 from Holz Morots Hales Corners Wisconsin. My truck was purchased in 2020 and I recieved the full 6 year warranty vehicle currently has 57,000 miles. Im within 60,000 drive train warranty. Dealer claims TSB is not part of the drive train warranty therefor not covered. How's that possible, a drive train is damaged by excessive heat and the thermo bypass valve of 198, creates excessive heat in the transmission destroying countless chevrolet transmissions. My position is: if the Thermo Bypass transmission vlave is not part of the drive train, then what is it doing in my transmission which moves the vehicle? I want to file a complaint, I want Chevrolet to stand behind the product they built and sold. Dodging responsibility on technicality is how Chevrolet will lose buyers. I'm very unhappy with the way I was treated with zero responsibility for the GM product. The dealership would not provide any type of discount.. too add insult to injury the dealer charged me a diagnostic fee after lengthy conversation on the problem which is absurd and offensive to any consumer. I paid and I said to myself, Chevrolet just lost a great customer because of a lousy policy claiming the thermo by pass valve is not part of the drive train... Bleed the consumer for a repair on the failures created by the manufacturer. Its under warranty on top of it all.. Best Regards [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA)

- Wauwatosa, WI, USA

Bad torque converter cause transmission to totally fail. Had chevy do transmission flush,2 yrs ago. Back in Aug 2024, transmission started to slip, while driving, then totally failed, no forward or reverse gears, nothing, had truck towed into chevy dealer, almost $7000 later, transmission had to be replaced.

- Liberty, IN, USA

Transmission failed at approximately 120,000 miles. All maintenance had been done and 90% of miles on vehicle were highway miles. Appears as though there's a thermostat mounted on the exterior of the transmission that is prone to failing around the 100,000 mile area, and when this part fails, there is no transmission fluid circulating to be cooled, so the transmission gets so hot it fails. There are tons of youtube videos from many GM owners that have had to spend thousands and thousands of dollars to replace the entire transmission, when General Motors knows of the faulty part.

- North Easton, MA, USA

Transmission locked up. Vehicle has low miles.

- Vinton, VA, USA

Had to replace rear end now transmission is starting to act up like might be going out (the truck started by like having a shake as you drive ot not for long period just every so often to when i gave ot rhe gas the really loud whinning noise let off gas it stopped )looked up to see if any others and many others with the same model as mine is having same trouble as I am and have not seen any recalls, but many people have been having same issues.

- Webster Springs, WV, USA

My transmission had a history of failing trans symptoms, all documented at the dealer from 10,000 miles until it ultimately failed at 127,000 miles. Those symptoms where a down-shift thud, confusion to what gear it should be in, shuddering, shaking and fluid temp running hot without towing a load. Was told by the dealer this was all normal, that the transmission was "still learning". Eventually the trans failed and was towed to the dealer. Dealer said that pieces of the torque converter were found in the fluid and building up in the filter, ultimately clogging it. I had all my recommended maintenance done at the dealer over the life of the truck. Once the trans failed I had an independent service center rebuild the trans, not wanting the same remanufactured trans that failed put back into my truck without any improvements made. No warning lights ever came on.

- Clarkston , MI, USA

Transmission failed and truck shut down mid road while going uphill. Shifting jumps when gears are switched and power jumps and goes down while stepping on gas pedal. At first it showed a check engine light but because i was traveling i had to skip and tried turning on again. It happened at least 5 times while on the road that day and now shifting is messed up and jumps while stepping on gas. I inspected and took to a mechanic for an inspection and said need a new transmission unless there is a recall because it happens to many 2018 chevy silverados 1500.

- Patterson, CA, USA

We just purchased the truck from a Chevrolet dealership 6 days prior took it on a trip to Missouri. Truck transmission shuddered then downshifted nearly causing a rear end accident behind us. Luckily the driver was attentive and did not hit

- Terre Haute, IN, USA

Transmission slipping and shuddering when fluid warms up. Dealership diagnosed torque converter/transmission failure. Stated it may cause transmission lockup while driving

- Terre Haute, IN, USA

Radiator replacement Thermostat replacement BG Coolant Exchange Mileage: 57,000 2018 -Silverado-1500

- St. Louis, MO, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving at an undisclosed speed, the vehicle stalled and lost motive power. The vehicle was taken to the dealer where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The contact stated that the engine and transmission were recently replaced, and the vehicle was released by the dealer and the failure occurred three days later. Additionally, the contact stated that the dealer installed a rebuilt transmission and engine, with a warranty up to 100,000 miles. The manufacturer was made aware of the failure and a case was filed. The contact stated that the repair was declined coverage under warranty. The failure mileage was approximately 41,000.

- Plainview, NY, USA

Unknown

- Albuquerque, NM, USA

Transmission jerks with hard shift and rough idle

- Stanton, MI, USA

My truck has had transmission issues since we purchased it. At 79,000 miles the factory transmission finally went out and needed replaced. The truck currently has 81,000 miles on it and is already having transmission problems with the rebuilt parts. Background: the truck began having hard downshifts since purchase. Over the course of our ownership, we noticed it started struggling with shifting from 2nd gear to 3rd and 3rd gear to 4th. Constant "clunking" and shuttering when trying to shift. Approximately November of 2024 the truck suffered from the known GM transmission failures. It was almost "skipping" upon acceleration and had a very hard time with cycling between gears. The transmission began making a sound comparable to a normal operating diesel truck (almost sounded like the turbo engines upon acceleration). The truck was sent to the dealership and the transmission was replaced. However, since this replacement we are now experiencing similar symptoms to the previous transmission. There is a very hard downshift, there is clunking sound when the truck is trying to go from 3rd to 4th, and the truck has a noticeable gear burning smell when driven long distances.

- St Maries, ID, USA

Transmission Failure & Torque Converter Clutch Failure, Less than 90,000 miles on vehicle. This is a known issue with this year and model truck that GM is aware of. It has been inspected by the certified dealer and they are aware that this is a known issue. I don-??t tow with my truck or do anything but drive it regularly. I was Quoted $8,900 with a $2,000 Core reimbursement.

- Rincon, GA, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving 35 MPH, the transmission failed to operate as designed and the vehicle started losing motive power. The contact stated that the vehicle returned to normal functionality afterwards. No warning lights were illuminated prior to the failure; however, the check engine warning light illuminated after the failure and remained illuminated. The vehicle was taken to an independent mechanic and was diagnosed with transmission failure. The failure persisted and the vehicle remained at the residence unrepaired. The manufacturer was notified of the failure. The failure mileage was unknown.

- Modesto, CA, USA