While driving at a steady speed, when attempting to lightly or moderately accelerate, a lack of power is noticed due to torque converter lockup. Engine comes close to stalling out. In May 2016, I was informed GM engineering was aware of the problem were working on a solution. During a followup visit in September 2016, I was informed that GM no longer considered it a problem and were no longer working on a solution. GM tac # 8-2110571583. There has not been a specific accident related to a lack of acceleration when expecting to accelerate, there remains the potential especially when merging into freeway traffic during peak travel times. The GM district service mgr drove the truck and informed me that there was no issue as he drove the same vehicle type and had the same performance. Per recent GM marketing, the 2017 GMC Canyon features a completely re-designed transmission. I believe this issue with the transmission is a safety issue caused by a poorly designed transmission.

- Fairview, TX, USA

I have same complaint as several others in the NHTSA customer complaint section. Basically the transmission fails to downshift at lower speeds causing the vehicle to hesitate when acceleration is needed until it downshifts appropriately. Pressing down hard on the accelerator will result in a downshift, but this is a potentially dangerous maneuver in crowed road conditions. I have also gone to manual transmission mode but this is also potentially dangerous in crowded conditions and certainly inconvenient. Seems the volume of this complaint warrants a GMC response.

- Eddyville, KY, USA

Have 20000 miles on truck and transmission still does accelerate smoothly.there is hesitation while transmission find right gear.while towing travel trailer transmission will accelerate but not deaccelerate till I reduce speed manually.very dangerous.

- Naples, FL, USA

The transmission does not down shift when climbing a small hill in normal traffic at normal speeds. I constantly have to use the manual transmission to make the truck downshift or I have to press on the grass in order to bring the RPM up a little higher using more fuel than required. This in itself is dangerous since I am in then middle of traffic. When I purchased the truck none of the recall were on carafe nor did the dealer inform me that this vehicle type and model has already had several recalls affecting its performance and safety. There is also something wrong with the defrost system whether its on heat or cool. There is a rattling noise that can be heard over the fan noise when the vehicle air conditioner is switch to the defrost mode. I am truly disappointed and very concerned for my safety. GM should have pulled this vehicle off the market!

- Saltillo, MS, USA

The truck does not shift properly, I experience rough shifts. It doesn't downshift, feels like truck is misfiring, and I experience slow throttle response. Overall I don't feel safe in this truck and sincerely regret my purchase. I've given the transmission a chance to break in and learn, but it's a real problem.

- Pine Brook, NJ, USA

Vehicle will not down shift when slowing from a higher speed and then needing to accelerate. Vehicle will "chug" and squat until it eventually down shifts, often times through two or more gears causing over acceleration and over revving of engine. Couple of times when coming to full stop at stop sign, vehicle stays in 5th or 6th gear upon acceleration for a few seconds and then jumps gears to pick up speed. Driving on cruise in moderate hills, vehicle will not down shift soon enough until eventually enough speed is lost that vehicle down shifts multiple gears from approximately 1800 RPM to well over 3000. Problem manifests itself in both city and highway driving.

- Godfrey, IL, USA

Transmission does not shift properly will not down shift hesitating and feels like truck is misfiring ruff shifts clunking sound problems start at about 20 mph when trying to speed up in traffic truck will not down shift or will downshift to violently causing truck to lundge forward and nearly rear-end car in front this is dangerous and could cause an accident GM seems to be ignoring this problem even though there seems to be quite a few people with the same complaint

- Darien, IL, USA

At low speeds, doesn't matter if you are turning or going straight, the transmission will not shift properly when applying pressure to the gas pedal. It feels like you are driving a manual transmission in 4th gear when it should be in 2nd. When it does shift, it will drop two gears and you could be on top of the car in front of you. The Canyon's transmission is not predictable and could put you in a dangerous position in traffic. Have had the vehicle at the dealer where they applied an update per a GM bulletin, helped some but still have the problem. Transmission makes a terrible grinding/howling noise at low speed. GM says this is a normal characteristic of this truck, I say it is dangerous. GM needs to better address this problem than they have. This happens everyday the truck is driven.

- Little Rock, AR, USA

While driving at low speeds the transmission seems to float between gears as if trying to find the proper gear. Normally it takes so long that I have to push down on the gas to force the truck to shift. It does to a lower gear which makes it jump from the excess power. At high speeds, pressing on the gas pedal is non responsive as the transmission continues to look for the right gear. A manual fix for safety purposes (especially in traffic and need an answer from my transmission) is to change it to manual shifting where I control the gears. This is a band aid fix at the moment and is quite interesting that I am able to shift my vehicle better than a computer. Please look into this issue. I am going to take it to the dealership but as I read in the numerous reports from other 2015 Canyon owners....GMC is not admitting or does not have a fix. This issue occurs all the time so selecting a date of when this issue happened is not effective.

- Prescott, AZ, USA

The truck chugs and hesitates randomly when a down shift is required. Generally this random hesitation is just annoying. At times the vehicle will not downshift for a considerable time. When making maneuvers in and around traffic the trucks poor shifting causes the truck to jerk and not accelerate. When the truck will eventually does down shift the gas pedal must be all the way at the floor and accelerates at full speed. Bulletin pip5342A supposedly addresses the concern but says it is normal. GM tells the dealer not to attempt to fix. I have had multiple times where this problem has put me at risk for an accident.

- Pleasant Prairie, WI, USA

I would just like to add my truck to the complaints. I am at 24000km on my Canyon and the transmission still hasn't learned anything. The transmission problems are the exact same as the other complaints on here. Its horrible and unsafe driving this truck everyday in the city. This issue needs to be taken care of before an accident does happen. Issue: Transmission programing

- Okotoks, MT, USA

Vehicle upshifts too early at low speeds requiring additional accelerator input then downshifts 2 gears to compensate. This happens regularly when going around 15-20 miles an hour uphill or while making right turns while vehicle is in motion. When the vehicle is searching for the correct gear the accelerator pedal is numb for at least 2 seconds requiring at least 90 percent throttle then it finally picks a low gear and violently throws the driver and passengers back and roars to life. The 2 or more seconds of hesitation could be very dangerous in an emergency situation when quick acceleration is needed. My concerns were voiced to bowser Buick GMC on 02/02/2015 during my first oil change. They informed me that GMC is working on programming for the Sierra right now and when it's satisfactory, they will implement it on the Canyons. No repair attempts were made to address this concern. They refused to make any repairs and said that I was added to a list of others with similar complaints.

- Pittsburgh, PA, USA

Vehicle upshifts too early at low speeds requiring additional accelerator input then downshifts 2 gears to compensate. This happens regularly when going around 15-20 miles an hour uphill or while making right turns while vehicle is in motion. When the vehicle is searching for the correct gear the accelerator pedal is numb for at least 2 seconds requiring at least 90 percent throttle then it finally picks a low gear and violently throws the driver and passengers back and roars to life. The 2 or more seconds of hesitation could be very dangerous in an emergency situation when quick acceleration is needed. My concerns were voiced to bowser Buick GMC on 11/20/2015 during my first oil change and they provided me with service bulletin #pip5342 which states "shudder or chuggle when accelerating at low speeds of 12-15 mph in second gear is normal operation of the automatic transmission and the torque converter clutch. No repair attempts should be attempted to address this concern" they refused to make any repairs and said that I was added to a list of others with similar complaints.

- Pittsburgh, PA, USA

Vehicle shifting lags and hesitates then engages abruptly causing unsafe acceleration. Specifically entering an on-ramp. When trying to merge into traffic from a slower ramp speed to join highway speeds the vehicle struggles to find the proper gear. In order to offset this problem the driver needs to depress the accelerator further to help the transmission downshift to a lower gear. However, doing so while the transmission is searching for the proper gear causes the vehicle to suddenly lurch forward with more force and acceleration then is required or safe. I have brought my truck into the dealership twice for this issue and was told that GM states that this is the normal operating conditions of the truck. I feel this is not an adequate response and certainly does nothing to address the safety issue of a transmission that disengages to search for a proper gear and then reengages abruptly causing the driver to make unnecessary and unsafe adjustments to keep the vehicle under control.

- Wilmington, DE, USA

I purchased this truck 3 months ago and it had around 9000 miles on it at the time of the incident. I was driving at around 25 mph when I noticed smoke coming from under my hood. I pulled over, shut the engine off, and popped the hood. I opened the hood and noticed the engine was on fire. Opening the hood just enraged it more. I slammed the hood shut, and got to a safe distance and called 911. Within minutes the truck was engulfed in flames. After the fire was put out, the firemen said it appeared to have started in the vicinity of the alternator. The bracket was melted off and all that was left of the alternator was a basket of copper. Everything minus the bed was on fire.

- Belpre, OH, USA

Transmission does not down shift at speeds between 27 mph and 40 mph, at 30 mph you have to put pedal to the floor then it will shift and tachometer goes around 4000 and takes off like a dragster.watch out for the guy in front of you! now hit the brakes, real cute. Dealer tested said yes it does it but we need a tsb before we can do anything called GMC they said file a complaint with NHTSA that I think is pretty cute also $ 38000 and your told to file a complaint. @carcomplaints.com people already there complaining also [xxx] information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).'

- Catskill, NY, USA

I wanted to reach out to you on GMC's claim that their engine achieves 305 horsepower. While it may be true that their engine achieves this figure it does so at a stated 6800 RPM. The 6800 figure is important to note because the trucks" red line indicating potential dangerous operating conditions start at 6500 RPM. So in essence in order for an owner to achieve 305 hp they would have to be operating their truck in a potentially dangerous manner. Even in the 2015 Colorado owner?S manual it indicates the danger of operating above the redline? ?do not operate the engine with the RPM?S in the warning area.? GM is stating that someone can achieve maximum hp only by operating the vehicle in a dangerous manner....really"! I believe it will only be fair for GMC to re-evaluate their maximum horsepower prior to their engine hitting the redline.

- Costa Mesa, CA, USA