Check Engine Light came on with message of "Steering Assist is Reduced Drive with Care". This same thing happened to my sister-in-laws 2019 Acadia 2 months earlier. Took it in right away to the dealership to find out it's the thermostat, it's a common/known issue and it isn't covered under my extended warranty and will cost ~$1300. I'm seeing this is a common issue for Acadia's and has not had a recall, don't understand why. It's one thing if this is a easy part to replace, but GM has made it so that most people now need a dealership or auto repair shop to fix it.

- New Baden, IL, USA

I'm going to have to replace my thermostat and most likely my sensor. It will pop up saying (steering assist is reduced drive with care) my temperature gage on my dash will sometimes will not go up, my heat is acting funny. I've had also when I put it in park saying it's not actually shifted into park.

- Blue Springs, MO, USA

Thermostat is repeatedly going bad. Throws Steering Assist reduced. Had it replaced twice and it-??s bad again.

- Covington, GA, USA

I bought a car about 2 months ago and they did not tell me the thermostat was bad and they won-??t cover it.

- Baxter, KY, USA

Car stalls and transmission dies

- Orlando , FL, USA

Due to negligence of gmc wright of wexford during the replacement of 3rd new transmission they did not clamp a hose together causing coolant to leak and my thermostat to come on n off. Causing further damage to my vehicle

- Avella, PA, USA

Unknown My 2019 Acadia Denali has/is been repaired 6 times in 1 1/2 years for engine oil leaks, has had transmission repairs twice, radiator repair and replacement. Also suspension warranty work as well. I feel the oil leaks is and has been excessive and dangerous due to no warning lights never displayed to alert me to check oil

- Las Vegas, NV, USA

Last week, the coolant gauge, on our 2019 GMC Acadia, was reading below "C".... The "Steering Assist" warning was disabled on the on-screen display and the Air conditioning stopped working. Took the car to a mechanic, who read the codes.... Mechanic stated that all symptoms were based on a defective GM thermostat. The thermostat was "stuck-open" causing the "steering assist" to be disabled as well as the A/C from being disabled as well. It seems GM has updated the part since when the series of Acadia were manufactured. After getting it repaired, at of our pockets, we researched and noticed that thousands of other GM Acadia owners had the same exact 3 symptoms: (1) malfunctioning coolant reading (2) "Steering assist" disabled (3) a defective ("stuck-open") thermostat..... Symptoms were exactly the same for all parties involved. We have owned many vehicles never had a thermostat fail before 65k Miles.... It became a safety issue since the car disables the "steering assist" based on the thermostat being stuck open. Contacted GM corporate which stated unless a recall, there would be no compensation. GM needs to make it right for the thousands of GM owners whose car has the 3.6L engine In short, this is a major issue since the car's steering system is NOT working correctly We would like a recall to be initiated. Thank you.

- Wantage, NJ, USA

Shift to Park Vehicle does not recognize the gear shifter is in the park position. Vehicle does not fully shut down.

- Bastrop, LA, USA

My coolant thermostat went out, causing my AC and steering assist to stop working. I have spoke to multiple other people who have had this same issue with their GMC Acadia and I believe this should be a recall. It-??s going to cost me $1200 to have this issue resolved.

- Groves, TX, USA

Component: Shifter Assembly & jumper harness Safety concern: Can't turn off vehicle - Carbon Monoxide poisoning, physical safety when parking not at home, as I would have to leave vehicle running... Message in dash was present when I brought vehicle to dealer. Dealer also replicated No inspection other than dealer. Part returned to me. Warning message has been coming on for past 60 days or so, progressively getting more frequent I receive a 'shift to park' message in telltale after I have shifted to park. At times, vehicle will not shut off until shifter is manipulated for several minutes. I have concerns that I cannot park vehicle in garage, if I cannot shut it off. GM is well aware of issue, but has yet to recall them. Dealer actually had replacement shifter in stock for a same day repair.. I was charged $778.98 for the repair, and GM's customer assistance center response to me simply was to file a complaint with NHTSA. My wife does not feel safe driving, as there is no guarantee vehicle will turn off. Dealer replicated issue when I brought to dealership. Dealer has replaced part and has them. Warning lights only appeared when problem reared itself, initially began about 60 days ago, but is not occurring on approximately 2 of 3 shut downs.

- Clinton Township, MI, USA

While driving the thermostat will go to zero and the steering assist is disabled. I have read a lot of forums that this is a known issue. The only way to reset it, so we have A/C is to disconnect the battery and it will last a day or two and do the same thing.

- Clayton, NC, USA

My 2019 GMC Acadia with 33,000 miles on it started to give me a notification to "Shift to Park" even though I had already shifted the vehicle into park. A "ding! ding! ding!" alarm wouldn't go off and the vehicle wouldn't turn off unless I repeatedly changed the gears until it read it was in park. This went on for a few weeks and got progressively worse. I read on a GMC forum that the vehicle could slip out of gear while driving and potentially cause an accident. My mechanic found the shifter assembly to be defective and replaced the entire Gearshift Lever Assembly. He said there was a plastic piece in the gearshift that snapped off and said this was an issue in the older models but thought GMC had fixed this issue by 2019. Unfortunately, I was past my 3 year / 36K mile warranty and had to fork over $1300 to have it repaired.

- Rochester, NY, USA

Our 2019 was repaired back in 2021 for a "shift to park" issue. This same issue is happening again after 2 years of being repaired. We see that there is a major issue with GMC vehicles and there have been recalls for this same exact issue. GMC Coleman, Lawrence NJ is refusing to fix problem under a recall. We would like this to be covered or reimbursed.

- Princeton Jct, NJ, USA

Code 0128 coolant temperature sensor failure triggered reduced lane departure assist

- Mesa, AZ, USA

The contact owns a 2019 GMC Acadia. The contact stated while the vehicle was parked, she noticed that the engine caught on fire with no warning light illuminated. The fire was put out by the Chicago Fire Department and after the vehicle was inspected the cause of the fire was determined as a failure with the electrical system. A police report was filed with the Chicago Police Department and a report was provided. No injuries occurred and no medical attention was needed. The vehicle was not towed. The dealer was contacted, and the vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 65,000.

- Chicago, IL, USA

The contact owns a 2019 GMC Acadia. The contact stated while driving at undisclosed speeds, the "Steering Assist - Reduce Speeds" message was displayed, and there was a loud roaring sound coming from the engine. The contact stated that the check engine warning light was illuminated. The failure recurred while the heat was turned off in the vehicle. The vehicle was taken to an independent mechanic where it was diagnosed with a faulty temperature gauge. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 80,000.

- Greenland, NH, USA

In August 2021, I placed my vehicle in park and pressed the vehicle on/off button and received a message on the dashboard that stated "Shift to Park", even though the vehicle was in the off position. I was unable to turn my vehicle completely off (remained in auxiliary mode) and unable to lock the vehicle. I took my vehicle to a Chevrolet dealer who notated the issue was inspected and verified with a repair procedure under TSB 19-NA-206. The service record reads "This condition is caused by the park switch in the transmission control not pulling BCM signal low to electronically show part position. Removed and reinstalled transmission control, installed new shifter harness and added wire harness jumper". In February 2024, the repairs completed by the dealer failed again, and this time the entire shifter (transmission control) needed to be replaced. The TSB that GM has put forth does not "fix" the issue, just puts a temporary band-aid on the problem until the vehicle is out of warranty and the customer is forced to pay for the repairs themselves. Without the vehicle registering it is park, the vehicle stays active and the customer is unable to lock or secure the vehicle, putting the safety of the customer at risk. It is also unknown if the vehicle is actually in park, putting those around the vehicle in danger of getting run over.

- Hatboro, PA, USA

Engine consuming extra oil due to failed piston ring. Also, may be the cause of a coolant failure code. Burning through excessive oil and check engine light came on. Also, prior to these warnings, I've felt hesitation when accelerating and when the car changes gears. I was told by a shop that I need a new engine. This causes a dangerous situation because the car could just stop working while driving or in traffic.

- Castleton, NY, USA

My 2019 GMC Acacia SLT would not go into park to allow me to shut off my vehicle. It ran for over an hour before it finally went into park. This was dangerous as I had a young child to pick up in a busy part of town and I had to leave it running to try to get help. With a 3 year old child this was crazy. This is not the first time it has done this. My car had a recall and whomever fixed it didn-??t do it. I feel this needs to be fixed properly now.

- Eau Claire, WI, USA