2018 Chevrolet Colorado problems

UNKNOWN OR OTHER

When shifted into drive, transmission hesitates to accelerate. Not all the time, some of the time.

NHTSA complaint #11757566 — an unverified report by a vehicle owner.

POWER TRAIN

While driving at normal and safe highway speeds, without warning (no audible or visual warning from the vehicle information display) my vehicle experienced engine lockout, loss of all non-electric power, and no control over vehicle speed. A few seconds after loss, the information display did show a "check engine light" and that the engine was in "lockout." We (my spouse, young child, and self) were surrounded by multiple commercial semi-trucks and passenger vehicles and had to weave and serve to avoid collisions at highway speeds and get to the shoulder of the highway in a few seconds. The root cause as diagnosed by a Chevrolet Dealership Service Department was failure of the magnetic strip that is press fit to the reluctor (tone) wheel. A 1/2in piece of the magnetic strip was missing and over 10 cracks within the strip itself observed. This magnetic strip is used by the Engine Control Module to measure engine RPMs. The strip's failure caused the EMC to shutdown the engine without warning which is a significant hazard for controlled vehicle movement at highway speeds. My vehicle's engine (LWN) is one of the few GM designs that have the press fit magnetic strip reluctor wheels. The rest use integrated wheels with the crankshaft or traditionally stamped steel with machined teeth. The vehicle and reluctor wheel has not been inspected by GM or any other representatives. I offered to send images to GM for records but they declined.

NHTSA complaint #11754282 — an unverified report by a vehicle owner.

ENGINE

While driving at normal and safe highway speeds, without warning (no audible or visual warning from the vehicle information display) my vehicle experienced engine lockout, loss of all non-electric power, and no control over vehicle speed. A few seconds after loss, the information display did show a "check engine light" and that the engine was in "lockout." We (my spouse, young child, and self) were surrounded by multiple commercial semi-trucks and passenger vehicles and had to weave and serve to avoid collisions at highway speeds and get to the shoulder of the highway in a few seconds. The root cause as diagnosed by a Chevrolet Dealership Service Department was failure of the magnetic strip that is press fit to the reluctor (tone) wheel. A 1/2in piece of the magnetic strip was missing and over 10 cracks within the strip itself observed. This magnetic strip is used by the Engine Control Module to measure engine RPMs. The strip's failure caused the EMC to shutdown the engine without warning which is a significant hazard for controlled vehicle movement at highway speeds. My vehicle's engine (LWN) is one of the few GM designs that have the press fit magnetic strip reluctor wheels. The rest use integrated wheels with the crankshaft or traditionally stamped steel with machined teeth. The vehicle and reluctor wheel has not been inspected by GM or any other representatives. I offered to send images to GM for records but they declined.

NHTSA complaint #11754282 — an unverified report by a vehicle owner.

POWER TRAIN

I purchased the truck at the end of March 2025. Within a few weeks I was noticing different issues in the transmission. It would occasionally shudder, have jerky or long shifts, would jump gears and lose power. The shudder was random but mostly on the highway, the jerky or long shifts would mostly occur when the egjne was cold and more often in cold weather. The lose of power and jumping gears would occur when towing and when I was in the mountains, once losing power as I was turning onto a major highway. I took the truck in three times to get diagnosed but they couldnt replicate the issue or find a code. I finally decided to pay for a flush with the fluid that was recommended by a TSB. After the flush the issues were then replicated by the service techs. I have an extended warranty. The representative then inspected the truck and found the same issues and approved a transmission replacement. I took the truck in on June 22nd 2026. As of July 21 the dealership is still waiting for the replacement transmission to be shipped from GM.

NHTSA complaint #11751922 — an unverified report by a vehicle owner.

POWER TRAIN

66,500 miles transmission shudder. Scenic Chevrolet advised the torque converter failed and damaged the transmission.

NHTSA complaint #11750843 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM:IGNITION

The contact owns a 2018 Chevrolet Colorado. The contact stated that while the vehicle was parked, the key was difficult to remove from the ignition. The dealer was contacted and informed that the shift interlock switch failed to recognize that the transmission was shifted to park(P). The vehicle was not repaired. The manufacturer was contacted, but offered no assistance because the vehicle was not under warranty. The failure mileage was approximately 60,000.

NHTSA complaint #11750525 — an unverified report by a vehicle owner.

VEHICLE SPEED CONTROL

My 2018 Chevrolet Colorado diesel has had repeated diesel emissions/DPF-related failures that cause the vehicle to enter reduced-power or limp mode. This is a safety issue because the truck suddenly loses power and cannot accelerate normally. The most serious incident occurred while driving over Santiam Pass in Oregon. The vehicle went into reduced-power/limp mode on a mountain highway, leaving me unable to maintain normal speed or accelerate safely. I lost power needed to pass traffic and had limited ability to respond to road conditions. The problem has happened several times. It has also occurred while I was towing my boat, which left me unable to continue the trip safely and created a hazardous situation because the truck could not maintain normal towing power. The issue appears related to the diesel particulate filter/emissions system and repeated DPF/regen or exhaust aftertreatment problems. I am concerned that a design, calibration, or emissions-system defect is causing sudden power reduction during normal driving and towing. This creates an unreasonable safety risk, especially on mountain passes, two-lane highways, and while towing. I am requesting that NHTSA review this as a potential safety defect involving the 2018 Chevrolet Colorado diesel DPF/emissions system and reduced-engine-power strategy. I am also requesting that this complaint be considered with any similar complaints, recalls, technical service bulletins, or emissions campaigns related to DPF regeneration, particulate matter sensor diagnostics, reduced engine power, or limp mode on the 2.8L Duramax Chevrolet Colorado.

NHTSA complaint #11748528 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

My 2018 Chevrolet Colorado diesel has had repeated diesel emissions/DPF-related failures that cause the vehicle to enter reduced-power or limp mode. This is a safety issue because the truck suddenly loses power and cannot accelerate normally. The most serious incident occurred while driving over Santiam Pass in Oregon. The vehicle went into reduced-power/limp mode on a mountain highway, leaving me unable to maintain normal speed or accelerate safely. I lost power needed to pass traffic and had limited ability to respond to road conditions. The problem has happened several times. It has also occurred while I was towing my boat, which left me unable to continue the trip safely and created a hazardous situation because the truck could not maintain normal towing power. The issue appears related to the diesel particulate filter/emissions system and repeated DPF/regen or exhaust aftertreatment problems. I am concerned that a design, calibration, or emissions-system defect is causing sudden power reduction during normal driving and towing. This creates an unreasonable safety risk, especially on mountain passes, two-lane highways, and while towing. I am requesting that NHTSA review this as a potential safety defect involving the 2018 Chevrolet Colorado diesel DPF/emissions system and reduced-engine-power strategy. I am also requesting that this complaint be considered with any similar complaints, recalls, technical service bulletins, or emissions campaigns related to DPF regeneration, particulate matter sensor diagnostics, reduced engine power, or limp mode on the 2.8L Duramax Chevrolet Colorado.

NHTSA complaint #11748528 — an unverified report by a vehicle owner.

FUEL/PROPULSION SYSTEM

My 2018 Chevrolet Colorado diesel has had repeated diesel emissions/DPF-related failures that cause the vehicle to enter reduced-power or limp mode. This is a safety issue because the truck suddenly loses power and cannot accelerate normally. The most serious incident occurred while driving over Santiam Pass in Oregon. The vehicle went into reduced-power/limp mode on a mountain highway, leaving me unable to maintain normal speed or accelerate safely. I lost power needed to pass traffic and had limited ability to respond to road conditions. The problem has happened several times. It has also occurred while I was towing my boat, which left me unable to continue the trip safely and created a hazardous situation because the truck could not maintain normal towing power. The issue appears related to the diesel particulate filter/emissions system and repeated DPF/regen or exhaust aftertreatment problems. I am concerned that a design, calibration, or emissions-system defect is causing sudden power reduction during normal driving and towing. This creates an unreasonable safety risk, especially on mountain passes, two-lane highways, and while towing. I am requesting that NHTSA review this as a potential safety defect involving the 2018 Chevrolet Colorado diesel DPF/emissions system and reduced-engine-power strategy. I am also requesting that this complaint be considered with any similar complaints, recalls, technical service bulletins, or emissions campaigns related to DPF regeneration, particulate matter sensor diagnostics, reduced engine power, or limp mode on the 2.8L Duramax Chevrolet Colorado.

NHTSA complaint #11748528 — an unverified report by a vehicle owner.

STEERING

Power steering failure, without incident. It started one morning, after turning off truck the previous day. Warning lights displayed as soon as truck was started. Very difficult to turn steering wheel. Too dangerous to drive. Dealer indicated the steering rack should be replaced.

NHTSA complaint #11742439 — an unverified report by a vehicle owner.

POWER TRAIN

Engine fails it violenty thumps and studders and drops from highway speed with no warning. This is a mfg. defect and also an EXTREME SAFETY CONCERN. The engine studders and thumps and we were almost rear ended by a truck when our truck could not go into gear properly. It is very scary! Dealership confirmed that they have many vehicles with same issue and recommended a Super Flush of transmission but not sure this will correct problem or cause more problems. There is no warning when these incidents occur and the driver has no control to avoid it. It is commonly referred to as the Chevy thump and studder and a known mfg defect in which GM refuses to pay for repairs causing consumers an extreme hardship! This is an ongoing issue affecting thousands of vehicles and someone is going to die! There is no negligence of operator of vehicle, it is a manufacturing defect that affects thousands of GM vehicles and they are doing NOTHING about it except expecting customers to keep incurring cost to try to remedy a repair at our own expense which is unfair! The government needs to force a recall at GM's expense!

NHTSA complaint #11741750 — an unverified report by a vehicle owner.

UNKNOWN OR OTHER

Engine fails it violenty thumps and studders and drops from highway speed with no warning. This is a mfg. defect and also an EXTREME SAFETY CONCERN. The engine studders and thumps and we were almost rear ended by a truck when our truck could not go into gear properly. It is very scary! Dealership confirmed that they have many vehicles with same issue and recommended a Super Flush of transmission but not sure this will correct problem or cause more problems. There is no warning when these incidents occur and the driver has no control to avoid it. It is commonly referred to as the Chevy thump and studder and a known mfg defect in which GM refuses to pay for repairs causing consumers an extreme hardship! This is an ongoing issue affecting thousands of vehicles and someone is going to die! There is no negligence of operator of vehicle, it is a manufacturing defect that affects thousands of GM vehicles and they are doing NOTHING about it except expecting customers to keep incurring cost to try to remedy a repair at our own expense which is unfair! The government needs to force a recall at GM's expense!

NHTSA complaint #11741750 — an unverified report by a vehicle owner.

ENGINE

Engine fails it violenty thumps and studders and drops from highway speed with no warning. This is a mfg. defect and also an EXTREME SAFETY CONCERN. The engine studders and thumps and we were almost rear ended by a truck when our truck could not go into gear properly. It is very scary! Dealership confirmed that they have many vehicles with same issue and recommended a Super Flush of transmission but not sure this will correct problem or cause more problems. There is no warning when these incidents occur and the driver has no control to avoid it. It is commonly referred to as the Chevy thump and studder and a known mfg defect in which GM refuses to pay for repairs causing consumers an extreme hardship! This is an ongoing issue affecting thousands of vehicles and someone is going to die! There is no negligence of operator of vehicle, it is a manufacturing defect that affects thousands of GM vehicles and they are doing NOTHING about it except expecting customers to keep incurring cost to try to remedy a repair at our own expense which is unfair! The government needs to force a recall at GM's expense!

NHTSA complaint #11741750 — an unverified report by a vehicle owner.

POWER TRAIN

Luggage and shudders at cruise speed, seems like auto transmission is coming apart. Paid $500 for the trans flush the service bulletin suggests but didn’t help, shop quoted a $8000 replacement on a vehicle with 60k miles. This should be a recall

NHTSA complaint #11714360 — an unverified report by a vehicle owner.

FUEL/PROPULSION SYSTEM

7.5 amp to fuel injectors has blown 2 times unknow reason causing loss of power 1st time on country road then 2nd time on a highway it's a common problem from the Chevy Colorado forums regarding the 2.8l lwn engine

NHTSA complaint #11711662 — an unverified report by a vehicle owner.

POWER TRAIN

Highlighting a materials defect with the rear crankshaft reluctor ring on the 2.8 LWN Duramax, installed in the Army Infantry Squad Vehicle and the 2015-2023 Chevrolet Colorado, from which it is based. When the ring delaminates, due to age, the vehicle engine shuts off and no start, rendered dead lined, as the ECU can no longer "see" the crank position. Requiring the transmission to be removed to rectify the issue.  I was pulling a trailer up a hill on the freeway when my truck down shifted, in an effort to slow down for a bus that was merging unexpectedly and the truck died at speed. The increase in RPM initiated an unplanned, instant disassembly of the ring due to cracking on the material and increased centrifugal force, shutting off the engine without warning, at speed. Again, just dead stick to the shoulder, towing a trailer, on the freeway. That could have been bad... Had truck towed to GM dealer, for a month-long repair.

NHTSA complaint #11699149 — an unverified report by a vehicle owner.

POWER TRAIN

transmission is not shfting properly.Truck losses speed and shutters when trying to accelerate.Difficulty climbing hills.Especially dangerous when merging with traffic.Only 33,000 miles on my truck.GM should recall to address this much complained about issue.

NHTSA complaint #11698704 — an unverified report by a vehicle owner.

AIR BAGS

All the sensors seem to not be functioning correctly. Doesn't tell me the right measurements for the wheels, gas, over heating. Right front passenger door locks/unlocks when it wants. It chokes up when trying to accelerate. Theres a rattling noise that comes from under the car. First time I took it to the dealership, they stated it was a bolt that had come loose on the exhaust pipe. They placed a new one which lasted a year and a half and now its back to making the noise. I took it again to the dealership, this time they claimed they couldn't find anything. My airbag sensor keeps coming on constantly. My fuel sensor claims 116 miles one moments and 5 or 6 minutes later, it says I have 50 miles. My car was over heating and low on Anti-freeze, the car never notified it was over heating.

NHTSA complaint #11694565 — an unverified report by a vehicle owner.

ELECTRICAL SYSTEM

All the sensors seem to not be functioning correctly. Doesn't tell me the right measurements for the wheels, gas, over heating. Right front passenger door locks/unlocks when it wants. It chokes up when trying to accelerate. Theres a rattling noise that comes from under the car. First time I took it to the dealership, they stated it was a bolt that had come loose on the exhaust pipe. They placed a new one which lasted a year and a half and now its back to making the noise. I took it again to the dealership, this time they claimed they couldn't find anything. My airbag sensor keeps coming on constantly. My fuel sensor claims 116 miles one moments and 5 or 6 minutes later, it says I have 50 miles. My car was over heating and low on Anti-freeze, the car never notified it was over heating.

NHTSA complaint #11694565 — an unverified report by a vehicle owner.

FUEL/PROPULSION SYSTEM

All the sensors seem to not be functioning correctly. Doesn't tell me the right measurements for the wheels, gas, over heating. Right front passenger door locks/unlocks when it wants. It chokes up when trying to accelerate. Theres a rattling noise that comes from under the car. First time I took it to the dealership, they stated it was a bolt that had come loose on the exhaust pipe. They placed a new one which lasted a year and a half and now its back to making the noise. I took it again to the dealership, this time they claimed they couldn't find anything. My airbag sensor keeps coming on constantly. My fuel sensor claims 116 miles one moments and 5 or 6 minutes later, it says I have 50 miles. My car was over heating and low on Anti-freeze, the car never notified it was over heating.

NHTSA complaint #11694565 — an unverified report by a vehicle owner.

POWER TRAIN

Transmission oil leak with only 60,000 miles just bought from a dealership as is 3 days ago and was not informed of the issue

NHTSA complaint #11677977 — an unverified report by a vehicle owner.

UNKNOWN OR OTHER

Saturday July 12, 2025: My truck got an ACTION Required notice: "Exhaust fluid Quality Poor See Owners Manual NOW 100 miles until 65MPH Max speed" I turned around and returned home to get a different vehicle to do what i needed to do. Monday, July 14 My mechanic hooked it up to the vehicle scanner and got the code information: "P11D5: NOx Sensor 2 Exceeded Minimum Learning limit (Symptom 00) - Current DTC, Test failed since DTC Clear, History DTC, Test not passed since power up, warning indicator requested" So we ordered and replaced the Sensor, still the action required message remains... I am now down to "64 miles to 55mph Max Speed" and my dealership is telling me there is nothing more that can be done, unless i want to pay up to 5k for additional repairs that in their experience may NOT fix the issue?? I've googled the issue and MANY MANY people complain of this issue and there appears to be no actual fix for it.... GM tells me that im out of luck and they have no information regarding a fix or remedy for the situation!

NHTSA complaint #11674487 — an unverified report by a vehicle owner.

UNKNOWN OR OTHER

The problem started two months ago, with a loss of engine power and a stability track warning on the dashboard. This happened occasionally while driving, often going away on its own by turning off the vehicle. Two weeks ago, I took it to Chevrolet for an inspection. They did a general inspection and said it was a factory defect. Now, the vehicle has the problem constantly, and there are times when it's undriveable. That's a risk for me.

NHTSA complaint #11671538 — an unverified report by a vehicle owner.

ENGINE

The problem started two months ago, with a loss of engine power and a stability track warning on the dashboard. This happened occasionally while driving, often going away on its own by turning off the vehicle. Two weeks ago, I took it to Chevrolet for an inspection. They did a general inspection and said it was a factory defect. Now, the vehicle has the problem constantly, and there are times when it's undriveable. That's a risk for me.

NHTSA complaint #11671538 — an unverified report by a vehicle owner.

POWER TRAIN

Clunking sound coming from rear end upon normal acceleration. When I take my foot off of the brake pedal, and depress the gas pedal, A loud clunk appears to come from the differential. If I coast first and then depress the gas pedal, it is not as pronounced. When you slow down to make a corner, and resume speed exiting the corner it is also pronounced. It should be noted that I am a safe adult driver (safe driver module installed in truck) and have 35,800 miles. My truck has always been serviced by my Chevrolet dealership; I am an older gentlemen and never drive recklessly. I'd like to think the rear differential should not be making a clunking sound at this point in its history

NHTSA complaint #11671441 — an unverified report by a vehicle owner.