On numerous occasions while entering/exiting vehicle my knee lightly brushes the 4 wheel drive engage switch located on the dashboard. This activates the 4 wheel drive on the vehicle. This is happening without my knowledge. Since there is no obvious indicator on the dash the the vehicle is in 4 wheel drive, if I do not notice the brief "engaging 4 wheel drive message" there is no way of knowing that it is in 4 wheel drive until the vehicle starts "hopping" on dry pavement while turning. Should this happen at highway speed on a curve there is the strong risk on a rollover. I have found myself having to regularly check the knob in order to determine if the 4 wheel drive is inadvertently engaged by this light brushing of the knob.

- Rosalie, NE, USA

"the transmission does not downshift from a high gear (5 or 6) to a lower gear when slowing down from 45 mph to 20 mph (or lower). When the accelerator is depressed to accelerate the engine bucks, vibrates, and does not accelerate. The engine RPM drops to 1,000 RPM or lower. If the accelerator is quickly floored the transmission downshifts several gears lower and jerks forward. This condition happens primarily on secondary roads while driving along the road and when pulling from one road into traffic on another road. The situation when pulling into traffic is dangerous because the truck does not accelerate as it should. This truck was purchased new and has 1200 miles on it. This condition has been present since the truck was purchased and the severity varies with truck speed and road inclination. I reported the situation to the dealer and they attempted a fix (had the truck for three days) that supposedly involved a "new download" from Chevrolet, but it didn't change a thing. Dealer knows it didn't fix anything and says Chevrolet may have a "recall update", but reading all the other similar complaints, I'm suspicious. In the 1 month I have had the truck, I have almost been hit twice by approaching traffic because of hesitant acceleration. This is a dangerous problem and Chevrolet need to fix it immediately. I

- Long Beach, CA, USA

I live in a rural area with moderate hills and many winding roads and tree obscured corners. While driving at a moderate speed (30-40 mph), I experience problems with the vehicle's ability to downshift from overdrive to address the increasing incline. The vehicle will, despite normal increase in fuel pedal pressure, lose RPM's from approximately 2,000 to 1,000. As it approaches 1,000 RPM, the vehicle begins to "stutter" and "lurch" as the engine tries to cope with the higher gear. There are two "fixes" for this; pushing the gas pedal down firmly, which causes the vehicle to radically down shift and "leap" forward, or to drop the transmission lever to "manual" and manually change gears (without the "leap" seen in the first method). The end result of the non-manual approach is to cause the vehicle to accelerate radically in an environment of obscured corners and uphill driving. I believe this is a dangerous safety problem as the area is swarming with deer, bicyclists, pedestrians, etc. I have also had "stuttering" incidents when accelerating from low speed, to enter traffic, interstate, etc., although these have been intermittent in nature. I have noticed that the vehicle will also radically downshift going downhill without warning and seems to take a long time to up shift once it is on level ground - again an intermittent action. Fortunately no one has been "tailgating" me when this occurs (a common failing of drivers in this area). I have had the vehicle to the dealer twice for the failure to downshift for a hill and they tell me Chevrolet does not recognize a problem with the transmission, shifting, etc. A side note: This problem does not exist in cruise control, but use of cruise control on these back roads would not be advisable.

- Warrens, WI, USA

Chevy said there are no fixes for the following complaints. Transmission is acceptable and smooth shifting under light loads. Under a need for downshifting for acceleration the down shifting is delayed or hesitates momentarily and then the truck jerks forward to a excessively lower gear & the upshifts to the gear it should have in the first place. The delay or lag in downshifting creates a very dangerous condition when needing instant power. There is much difficulty when merging into traffic when power is needed.. manipulating the manual shift can cover up this defect on some occasions when if you have time to plan for it. The transmission also shutters at low load many times resulting in no power until you downshift. Then this downshift is delayed and then becomes abrupt again. The shutter feels like the truck is going over small bumps in the road. The transmission shifting is certainly not correct and certainly results in unsafe situations. I should have test driven the truck under more conditions than I did and probably would not have purchased it. I hear that this problem can be fixed with an aftermarket computer update. Chevy probably dose not want to admit that in order to have the gas mileage ratings the transmission must bet this way. Also note that the 2017 Colorado will have an 8 speed transmission.

- Deer Park, NY, USA

Delayed or no downshift. Traveling about 2 mph and turning either right or left and applying throttle the truck does not respond until the throttle is increased steeply. The transmission does then shift to a much lower gear and acceleration is dramatic.

- Camp Verde, AZ, USA

2,400 miles and this vehicle has been back to the dealer four times for "chugging and shuttering" in heavy traffic. Driving though an intersection with heavy traffic it will not keep up with traffic but tends to bog down almost getting rear ended from behind. If you try to smoothly accelerate it will rapidly downshift and jump forward almost rear ending any vehicle in front. Very unsafe to drive. Trying to drive with the flow of traffic at 35-40 mph the truck shutters as if the spark plugs are worn out. Also trying to accelerate into on coming traffic it will sometimes chug to where you wonder if it's going make make the merge. Very frustrating to drive for a brand new truck, the dealer replaced the torque converter at 500 miles, then has preformed service bulletin #pip5342B three times with absolutely no improvement. GM states in the bulletin "note: Preforming this calibration update may not totally address the shudder or chugging concerns" how can new vehicles continue to be sold with this known problem? not only is it frustrating trying to drive smoothly, but it is also a safety concern. Due to the poor performance the mileage is about 13 mpg in city traffic, not even close to the mileage rating of 17 mpg.

- Cape Coral, FL, USA

While driving on a hilly highway at 55 mph, the truck suddenly lurched into an extreme downshift as I was going downhill. I had not been making any significant braking or acceleration motions--just driving normally with the flow of traffic and I had nothing in tow. The truck decelerated quickly and the rpms climbed significantly. This occurred twice: Once around 2,800 miles and a second time at 3,400 miles, under the same conditions - dry roads, daytime, going downhill on a highway. There were not any warnings, and none of the service lights came on. It would not shift out of this gear. Each time, I had to avoid being hit from behind, and pulled over to the side of the road to stop completely. Then I was able to proceed with normal functioning of the transmission. The cause is unknown.

- Norristown, PA, USA

While driving the 2016 Colorado, the transmission/engine seems to have trouble shifting and accelerating and the shift patterns are erratic it seems, maybe its the fuel efficient crap that shuts down cylinders, maybe its the trans?. experienced it on highways and lower speeds, stop and go traffic, truck's transmission clunks, shifts hard at random and stutters allot. It's aggrivating. When trying to pass, seems to be zero acceleration felt when flooring it then suddenly kicks in (roughly)..like oh hey-I need to go.. I could get in a wreck-ended because of this and I better not try to pass anyone.. I feel my safety could be at risk with as much hesitation then suddenly lurches as it has. I see quite a few complaints already concerning this and/or describing just about the same ordeal. Daily - but random - city and highway, turning, straight etc. Basically any situation but idle.

- Dayton, OH, USA

Vehicle stalls sometimes when I stop. SE light is now on. Service brake assist comes on now. Truck surges and shutters and is annoyingly hunting for gears and can't find them. Sluggish throttle like I'm trying to pull a bull dozer out of the mud. This mostly happens between 15 and 40 mph back roads and highway stop-N-go. Not settling for the "oh that's normal" bsht. Should have bought a Ford F150. Time for a trade in. 10K miles and I am completely disgusted with Chevy now. All I can say is good luck if you have a 2016 Colorado.

- Blairstown, NJ, USA

The transmission hesitates while trying to find the correct gear..I spoke to a maintenance rep at the dealership where I bought my truck and he said that the engineers made the truck that way for fuel efficiency. He also told me to just floor the accelerator to get power when I need it. It still hesitates even when I floor it and how does that help fuel efficiency? he said if a technical service bulletin comes out on this issue that I can bring in my truck and they will fix the issue. I am scared to pass a vehicle unless absolutely nothing is coming for fear of the time it takes for the truck to find the correct gear. It also kind of jerks when it does find the right gear. This has been going on since I purchased it in January of 2016.

- Bay St. Louis, MS, USA

On 6/6/16 I started having the trouble. After backing up and putting the truck in gear, the truck would surge forward without touching the gas pedal. This also occurred on 6/11/16, 6/17/16 and 6/23/16. On 6/23/16 I was at surdykes port 20 marina at the lake of the ozarks. After backing out of the parking space I put it in gear. This time it was much more than a surge. It literally shot forward and even the brakes didn't help because within 3-4 seconds my truck and I were in the lake. Finally got the window to break so I could escape. Just before I went in the lake the truck struck an old golf cart and jet ski trailer that were parked there and took them into the lake also.

- Crystal City, MO, USA

While driving the Colorado, the transmission gets so confused on what gear to be in and the shift patterns are the craziest I have ever experienced. From 40-20mph, stop and go traffic, this truck's transmission clunks, shifts hard, stutters and cannot figure out which gear to be in. It's very frustrating. Not to mention, when trying to pass, there is zero acceleration felt when flooring the peddle. I am so frustrated with this transmission and many days during the to and from work commute, I feel as if I am going to get rear-ended because of this transmission. It's annoying when driving but stressful as well, because I feel as if my safety is in jeopardy due to this "learning" transmission. It's so disappointing.

- Colorado Springs, CO, USA

--- "the transmission does not downshift from a high gear (5 or 6) to a lower gear when slowing down from 45 mph to 20 mph (or lower). When the accelerator is depressed to accelerate the engine bucks, vibrates, and does not accelerate. The engine RPM drops to 1,000 RPM or lower. If the accelerator is quickly floored the transmission downshifts several gears lower and jerks forward. This condition happens primarily on secondary roads while driving along the road and when pulling from one road into traffic on another road. The situation when pulling into traffic is dangerous because the truck does not accelerate as it should. This truck was purchased new and has 1,500 miles on it. This condition has been present since the truck was new and the severity varies with truck speed and road inclination. The situation has been reported to the dealer and to Chevrolet customer service. No corrective actions have yet to be made."

- Pittsfiled, MA, USA

When merging onto I-70 freeway from on-ramp, I applied throttle to move into the traffic flow. Engine "stumbled" as if in a dead spot. Truck did not accelerate and appeared to be lugging badly. Transmission was in too high a gear and seemed to be searching for correct gear. During this time oncoming traffic was forced to brake and there was a near miss of having a rear-end collision. All I could do was watch in the rear view mirror as traffic converged on me. This "dead throttle / wrong gear" issue has happened repeatedly on surface streets but luckily on surface streets I was not in such a critical situation. This is a problem that has been reported repeatedly and at many places on the internet. When will NHTSA force GM to address this issue? hopefully you will act before this results in serious injury or fatalities (if it already has not). Please act!

- Golden, CO, USA

Engine seems to lag under quick acceleration. Problem occurs most often when accelerating from a turn or when changing lanes under acceleration. Speeds of occurrence mostly approximately 20-25 mph. Requested checks and service at a dealership only to be given a service bulletin from GM stating this was a normal part of the traction management system. My previous vehicle (2014 Silverado) was also listed on the bulletin, but the problem was never noticed on this vehicle. I see this issue as an increased risk of a collision with the highest risk being a rear end collision. This needs to be addressed and fixed.

- Albuquerque, NM, USA

The transmission does not downshift from a high gear (5 or 6) to a lower gear when slowing down from 45 mph to 20 mph (or lower). When the accelerator is depressed to accelerate the engine bucks, vibrates, and does not accelerate. The engine RPM drops to 1,000 RPM or lower. If the accelerator is quickly floored the transmission downshifts several gears lower and jerks forward. This condition happens primarily on secondary roads while driving along the road and when pulling from one road into traffic on another road. The situation when pulling into traffic is dangerous because the truck does not accelerate as it should. This truck was purchased new and has 6,500 miles on it. This condition has been present since the truck was new and the severity varies with truck speed and road inclination. The situation has been reported to the dealer and to Chevrolet customer service. No corrective actions have yet to be made.

- Ashford, CT, USA

While driving the vehicle over 40+ mph and then reducing speed due to traffic to 20 mph, and then accelerating the engine again between 21-28 mph it seems to bog down the engine almost as if the transmission shifts into to low or high of a gear and makes the vehicle feel like it's bucking/jerking when trying to accelerate between 21-28 mph and then a burst of speed. Vehicle does it all the time between these speeds. Vehicle was bought brand new had it custom ordered and only had 9 miles on it so I know it's not a issue from someone else driving it vehicle currently has 1,200 miles is a V-6 crew cab

- Port Orange, FL, USA

Driving at about 60 miles a hour and lost all power engine was running but going no were all light were lite on dash like you turn key on before starting thank god no one was coming the other way or the car behind me would have hit me. He was a good driver. Shut it off and restarted it then it would run with all light on dash even brake light and anti skid light and it said on infro. Running at reduced speed. Drove to my home a slow speed it let me. Shut it down let it sit a few min. Restarted it still the same. Shut it down for about ten mim. Restarted it. Seem to run ok but check engine light is till on now I afraid the will just reset it and say it is ok. And next time I won't be so lucky. It has 5500 miles on it. I did see my life before my eyes hopping it dose not happen to others. Taking dealer tomorrow it happen at about 5pm 3/24/2016

- Harrisburg, PA, USA

Transmission does not downshift properly from upper gears (5,6) to lower range when decelerating from 40 + mph to under 20 mph. Vehicle will exhibit loss of power from being in too high of a gear range, causing "chugging", and then a sudden burst of power as you try to accelerate. Dealer reset ECM for transmission; problem persists. Typically occurs on residential or non-freeway streets, but has happened entering a freeway entrance ramp.

- Inver Grove Heights, MN, USA