An independent service center confirmed that the water pump failed and fell apart. This water pump is a 4-groove pulley (part number 12685259) specific to my vehicle. Most other Silverados have a 6-groove pulley system. This 4-groove pulley water pump is unavailable from the dealer or any of the part stores, as they are on back order with no resolution or availability date. GM has notified some parts stores that this part has been discontinued and is no longer available. This truck is less than 10 years old. There are no other parts, either aftermarket or otherwise, to replace my water pump. The water pump is a vital engine component needed to prevent significant engine damage, and without it, the truck can not run independently without overheating. It is essentially the heart of the automotive cooling system, because the truck water pump function is to continuously circulate the engine coolant from the radiator to the engine and back to the radiator. I have had my truck in an independent service center since January 2025, waiting for this part, which is unavailable. I do have the original part at the shop available for inspection. There were no warning lamps, messages, or other symptoms of the problem before the failure; it just started making a clanking sound, and I immediately took it to a shop, and have been out of a vehicle for 5 months.

- Anchorage, AK, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving 35 MPH, the vehicle went into LIMP Mode and was slow to respond as needed. The contact stated that there was smoke coming from the exhaust. While driving, the rear end locked up. The contact stated that the vehicle was slipping, and the vehicle shut off while driving. The contact stated that several unknown warning lights were illuminated. The contact replaced the spark plugs, coil pack, and spark plug wires with a misfire in cylinder #6. The contact stated that the fluids were replaced at an unknown local dealer prior to the failure. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 170,000.

- Haverhill, MA, USA

Engine all of a sudden had no power or acceleration. Started shaking and thumping extremely loud.

- Healdton, OK, 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

Lifter problem misfire

- Florence, MS, USA

Truck suddenly started slowing down and smoke came from the tailpipe. No warning issued before the failure. Transmission replaced in January of this year also.

- Clinton , LA, 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

I was driving on the interstate and then all of a sudden my vehicle started shaking while driving and by the time I got home in less than 15 miles, the truck was producing huge clouds of smoke out of the exhaust. I took it to a dealership and it was determined the lifters were bad, less than 6 months after I paid off my vehicle and the extended warranty expired. In repairing the lifters it was determined there was a misfire in cylinder 6 which in conjunction with the lifter failure, it damaged rods and pistons to such an extent full engine replace was deemed necessary. I had every maintenance and inspection done on time since the purchase of the vehicle by a local Chevrolet dealership and there apparently was no warning or concern that my lifters were going to imminently fail and/or cause extensive engine damage. My truck was in the repair shop for nearly a 1 year while I waited for a new engine Chevrolet agreed to pay for half of an engine even though I was out of warranty by a few months, but I was under the mileage on the warranty by 30k miles. The truck was not heavily used. Most miles were highway interstate miles from long road trips, but the vehicle largely sat undriven most days of the week for a couple years leading up to the engine failure.

- Portland, OR, 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

Entire system (everything) shut down without warning, sometimes kick back on, and other times not at all. Extremely dangerous as it will occur no matter traveling on highway or turning a corner in a parking lot. There are discussion boards in which many people have experienced this problem and clearly it is because of "Bad Battery Cables" and common within the 2014-2018 models. My truck is currently in a dealership garage to have the cables replaced and I have to have a rental car while the cables are on backorder for 5 to 10 days (maybe longer). How is this not a "recall" when so common and so dangerous? Dealership could see in a diagnosis that power had been lost and communication lost, over and over and over. There has never been a dash warning light come on at all.

- Shawnee, KS, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving at various speeds, the contact stated that the vehicle felt like the transmission was slipping. The contact stated that the transmission was shifting abnormally. Additionally, while the vehicle was stopped and idling with the brake pedal depressed, the RPM was fluctuating, and the vehicle was moving unintendedly. The contact stated that while attempting to accelerate the vehicle was jerking. The contact stated that the check engine and traction control warning lights were illuminated. The vehicle was taken to the dealer however, the dealer was unable to determine the cause of the failure. The dealer replaced the serpentine belt however, the failure persisted and became more persistent over time. The vehicle was taken to a certified mechanic who retrieved a DTC code for engine failure. The mechanic referred the contact to the manufacturer for assistance. The vehicle had not been repaired. The manufacturer was made aware of the failure and confirmed that the VIN was not under recall. The manufacturer referred the contact to the NHTSA Hotline to report the failure. The failure mileage was 92,000.

- Lynn, MA, USA

Two broken exhaust manifold bolts

- South Lyon, MI, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The contact stated that the vehicle was shaking and jerking. The contact stated that the vehicle failed to accelerate above 40 MPH. In addition, the contact stated while driving uphill, the failure reoccurred. The contact was almost involved in a crash because the vehicle had failed to accelerate. The contact stated that the vehicle rolled backward. The contact turned the vehicle off and restarted the vehicle and the contact was able to get to the shoulder of the road. The vehicle was taken to the dealer where it was diagnosed with engine and transmission failure. The contact was informed that the engine and the transmission needed to be replaced. The vehicle was not repaired. The contact stated that the failure had been occurring for over five years. The contact stated that the vehicle had been taken to the dealer several times due to the failure. The contact was informed several times that the failure could not be duplicated. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 27,000.

- Waianae, HI, USA

Hi i toke in my truck twice because of it was jerking was told it was fine noting was wrong my truck is now doing it so hard it feels like I been hit by another car

- Santa Rosa, CA, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving at an undisclosed speed, the vehicle shuddered abnormally. There were no warning lights illuminated. The contact stated the failure was present when the vehicle was first purchased; however, the failure had since gotten worse. The vehicle was taken to a local dealer however, the cause of the failure could not be determined. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 24,000.

- Corsica, PA, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving out of the driveway, the vehicle shuddered prior to stalling. The vehicle was able to be restarted; however, the contact was concerned for his personal safety while driving the vehicle after the failure. The vehicle was towed to a local dealer where it was diagnosed and determined that there was a misfire in cylinder #6, lifters, and guides needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 76,000.

- Oklahoma City, OK, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated that upon starting the vehicle, the contact heard an abnormal ticking sound coming from the engine compartment. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who diagnosed a failure with the exhaust manifold bolts. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 100,000. The VIN was not available.

- Reno, NV, USA

The contact owns a 2018 Chevrolet Silverado 1500. The contact stated while driving 10 MPH, the check engine warning light illuminated. The contact stated that the remote became inoperable. The vehicle was taken to the local dealer, and the contact was informed that the repair was not covered under a warranty or service bulletin. The vehicle was not diagnosed or repaired. The vehicle was taken to an independent mechanic, who stated that the motor on the active grill shutter was defective. The contact communicated with a GM engineer regarding the Technical Service Bulletin: PIE0500. The manufacturer was not notified of the failure. The failure mileage was approximately 48,000.

- Macomb, MI, USA