Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2017 GMC Acadia owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2017 GMC Acadia. The contact stated while driving at an undisclosed speed, the contact became aware that the steering wheel was inoperable, with the message "Steering Assist Reduced" displayed. The contact stated that the steering wheel was loosened and became difficult to turn. The vehicle was able to restart. The vehicle was taken to the dealer where it was diagnosed that the thermostat coolant sensor had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline for assistance. The approximate failure mileage was 80,510.
I brought this car from STOOPS and have been having this same issue since I received this car in March of 2021. Check engine came on within two weeks of me getting this car. The Intake air pressure measurement system MAP sensor and MAF sensor on my 2017 GMC Acadia which is causing other issues. My car is only at 100k mikes and I shouldnt be having the same issue. The MAP sensor was replaced in July of 2021. Here it is a year later and my check engine light keeps coming on and saying the same thing which is causing all these other issues to happen such as steering power system reduced which driving. Notifications about of transmission and engine issues because of Intake Air Pressure Measurement System. Every time I take it to stoops they have it for a couple days and I'm out of a car which means no transportation for work and within 10 days after I get it back the same issue appears. …
My vehicle has serious issues that from my research seem to be a common problem/manufacturer defect experienced by other owners of this model. I believe the defect/issue is an electrical problem. While driving, the vehicle will often have problems using it's automatic transmission. It ranges from "rough" shifting (where the car jerks while shifting gears) to situation where the vehicle fails to shift gears completely leading to the RPMs shooting up. The cars power steering and traction control system also simultaneously fail. This leads to a dangerous situation when on highways etc This issue simultaneously causes all of the warning lights on the dashboard to light up while displaying the following messages on screen "Service stabilitrak" & "steering assist reduced -drive with care" & "service brake assist" & "service parking brake". …
On [redacted] my 2017 Acadia Denali started driving poorly and a steering assist reduced message appeared. I had O'Reilly scan for error messages and they were: P0128 and P0826-00. The dealership confirmed that they would need to replace the thermostat. The Buick GMC Beaverton technician made a video of my vehicle: [redacted] My safety was put at risk due to the risk of my steering going out. My car intermittently was having trouble engaging in driving (it randomly acted like it was not firing, it was "jerking"), I heard my cooling fan come on immediately the next day when started my car to drive it to the GMC dealership. I feared that my car would just die going over a mountain pass without cell coverage. On [redacted] I had the same steering assist reduced message and then replaced my thermostat at 39,228 miles. I will need to replace this again, 37,638 miles later. …
While driving at highway speeds, a warning appeared on the Driver Information Center (DIC): "Steering Assist is Reduced - Drive with Care." Simultaneously, the temperature gauge was stuck on "C," the radiator cooling fan ran at high speed, and the air conditioning stopped blowing cold air. After researching the issue, I discovered that these symptoms are commonly linked to a failing thermostat-a known and widespread problem with GM's 3.6L LGX engine. Unfortunately, replacing the thermostat on this engine is not a simple repair, often requiring significant labor and cost. The most concerning aspect is the loss of steering assist, which poses a serious safety risk, especially at highway speeds. Given the frequency of this issue across many GM vehicles, it's clear that this is a defective part and not an isolated incident. …
The contact owns a 2017 GMC Acadia. The contact stated while driving at an undisclosed speed, the power steering assist warning light illuminated. The contact stated that the warning light then turned off independently. In addition, the contact stated that the air conditioning failed to function as intended and the interior of the vehicle became extremely hot. The vehicle was taken to the dealer; however, the failure was not duplicated. The contact stated the vehicle was taken to the dealer in 2024 for the failure, and the contact was informed that the power steering assist feature had failed, and the software needed to be updated. The vehicle was repaired; however, the failure reoccurred. The manufacturer was made aware of the failure. The contact was advised to contact the NHTSA Hotline to report the failure. …
P0128 Apparently what happens when the temp sensor on the T-Stat housing goes bad it sends a signal to the ECM that the engine is overheating, causes the temp gauge to peg to "C", shuts down A/C Compressor Clutch engagement to not exacerbate the Overheat condition and super speeds the cooling fans. Of course it's a false flag warning and the engine isn't actually running hot. At the same time a signal to the ECM also tells the Power Steering Rack that it's Super Cold out and the lube in the steering system may freeze up causing loss of steering assist. NHTSA 17-NA-158 - MAY 2017 Needed to have Thermostat and Temperature sensor replaced. Was quoted by two dealers $1400-$1700. Very deceiving for GM to have SEVERAL "tech bulletins" advising their techs how to properly diagnose this common "error"... but it's not a recall so they won't foot the bill for what is clearly a defect. …
Vehicle keeps intermittently coming up with "Power Steering Reduced: Drive with Care," during this my steering is perfectly fine, however my A/C stops blowing cold air, the temperature gauge stops working and my engine fan is running constantly. This is obviously a well known issue since googling that warning and my vehicle it comes up with the issue and what the cause is. Which the cause is from the thermostat remaining open and allowing coolant to run through the system, even when the vehicle is not overheating. I just bought this vehicle used from my local dealership and am surprised that GM has not recognized this is an issue affecting numerous vehicle. This should at the very least be put as a warranty covered issue!
Vehicle will randomly drop into a lower gear which causes the engine to rev up, then a warning light comes on indicating that the steering assist and ABS system are offline. Not what you want to have happen when driving 70MPH on the highway. Problem has been ongoing for ytears and GMC insists it is a transmission problem but another thing I have noticed whenever it happens is that the battery voltage increases. Seems like GMC shipped these cars with weak alternators which would explain the myriad electrical problems this vehicle and others like it have had.
I believe my vehicle has a software issue, the temperature gauge will read cold, I will get a "Steering assist reduced drive with caution" message, my A/C stops working, and the radiator fans come on full blast the moment you start the car because the temperature can not be read. I have read online forums where others are having this same exact issue. Resetting the codes seems to temporarily fix the issue, but it comes back within roughly 2 weeks. This vehicle has not even reached 60k miles yet.
Steering complaints in other Acadia years
Frequently asked questions
How common are steering problems on the 2017 GMC Acadia?
NHTSA has 34 complaints about the steering of the 2017 GMC Acadia, 5% of the model year's 705 complaints.
Is there a recall for 2017 GMC Acadia steering problems?
No. NHTSA lists no steering recall for the 2017 GMC Acadia, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2017 GMC Acadia steering problems start?
Half of the complaints with a recorded mileage happened before about 16,000 miles, and 56% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 0 fires and 0 injuries to steering problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.