This preliminary informational (PI) bulletin provides information to dealership personnel that may be helpful when addressing underbody component corrosion with customers.
full bulletin at NHTSA ↗2018 GMC Acadia steering problems
severe Owners of the 2018 GMC Acadia have filed 24 NHTSA complaints about the steering at roughly $700 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See steering across all vehicles →
Complaints
24
Recalls
0
Avg fix
$700
| Model year | steering complaints |
|---|---|
| 2014 Acadia | 26 |
| 2015 Acadia | 33 |
| 2016 Acadia | 26 |
| 2017 Acadia | 33 |
| 2018 Acadia (this page) | 24 |
| 2019 Acadia | 30 |
| 2020 Acadia | 17 |
| 2021 Acadia | 15 |
| 2022 Acadia | 3 |
2crashes
5injuries
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering steering on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This informational bulletin instructs the tech when fuel/fluid is needed to be tested and where it can be sent for analysis.
full bulletin at NHTSA ↗This service bulletin provides a procedure inspecting for excess grease or Sealant on the Exterior of the steering gear due to seeing grease or sealant on certain locations on the gear.
full bulletin at NHTSA ↗This informational bulletin explains Unscheduled Supplemental Services and the importance of GM Simplified Maintenance Schedules.
full bulletin at NHTSA ↗This service bulletin provides a vibration analysis worksheet the technician can use in conjunction with the appropriate Vibration Analysis-Road testing procedure when diagnosing vibration concerns.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners of 2018 GMC Acadias consistently report a cluster of safety-critical failures. The most frequent complaint is a "Steering Assist Reduced – Drive with Care" warning that causes the steering wheel to stiffen unexpectedly while driving. Owners cite OBD code P0128 (thermostat or coolant temperature sensor fault) as the underlying issue, yet even after replacing these parts, the warning recurs. When this happens, the A/C shuts off and the cooling fan roars to maximum speed.
Nearly as common is a "Shift to Park" malfunction: the vehicle refuses to recognize it's in Park, forcing owners to cycle the shifter repeatedly or jiggle the button to shut the engine off. This happens every time some owners use their vehicles.
Several owners report brakes becoming unresponsive in winter conditions, transmission slipping during highway driving, and unintended speed increases paired with brake failure (one case resulted in a multi-car accident with injuries). Battery and alternator failures have also surfaced, with one owner discovering oil everywhere after alternator replacement.
Owners repeatedly state that GMC has not issued recalls despite acknowledging these issues exist in earlier model years. Dealerships have blamed snow or weather rather than investigating defects. Multiple owners reference pending class action lawsuits and assert these are manufacturing flaws, not wear items.
Same GMC Acadia steering reports on nearby years: 2015 · 2016 · 2017 · 2019 · 2020
Failure modes owners describe
Steering Assist Reduced / Power Steering Assist Failure
Dashboard warning 'Steering Assist Reduced - Drive with Care' or 'Power Steering Assist Reduced' appears, accompanied by stiff steering wheel and reduced steering responsiveness. Multiple owners report this occurs randomly or repeatedly. OBD code P0128 (faulty thermostat or thermostat sensor) is cited as the underlying cause in several complaints; however, even after thermostat and coolant temp sensor replacement, the issue recurs. Owners report the steering becomes hard and stiff, creating highway safety hazards.
When: Various speeds, throughout vehicle operation; recurring even after repairs. One complaint at 105,000 miles.
Symptoms owners cite: Dashboard warning 'Steering Assist Reduced - Drive with Care'; Steering wheel becomes stiff and hard; Reduced steering responsiveness; Engine coolant temp reading of 0 degrees; A/C turns off when warning appears; Check engine light illuminates; Stability trac indicator lights up; Fan kicks on to high speed
Codes mentioned: P0128
Repairs/costs cited: Thermostat replacement, coolant temperature sensor replacement reported, but issue recurs. Infotainment system replacement mentioned in one case. Owners note the warning requires mechanic reset.
Recalls/TSBs owners mention: GMC informed owners 'no recalls on the VIN' despite owners citing same issues as recalled vehicles. Dealership blamed snow/weather in one case. No recalls appear to have been issued despite widespread complaints and class action suits mentioned by owners.
Shift to Park Malfunction
Transmission will not recognize or accept Park position. 'Shift to Park' warning message repeatedly displays on instrument panel even when the vehicle is already in Park and turned off. Owners must repeatedly cycle the shifter from Drive to Park or jiggle/squeeze the shifter button to clear the warning. Issue prevents vehicle shutdown and recurs frequently.
When: Occurs when shifting to Park and attempting to shut off vehicle; one owner reports occurring every time vehicle is turned off for over a week.
Symptoms owners cite: Dashboard warning 'Shift to Park' displays repeatedly; Cannot turn off vehicle initially; Must repeatedly shift from Drive to Park to clear warning; Must jiggle or squeeze shifter button repeatedly to reset warning; Warning recurs frequently, sometimes every use within 24 hours
Repairs/costs cited: No repairs documented in narratives; owners forced to manually cycle shifter or jiggle button.
Recalls/TSBs owners mention: No recalls issued; GM states affected VINs were 'not affected by the recall' despite owners reporting identical issues to recalled vehicles. One owner notes existing class action suits on this issue.
Electrical / Battery and Alternator Failure
Battery saver mode unexpectedly activates, causing dashboard lights to flicker and turn off, rendering vehicle immobile in traffic. One owner reports battery pulling 89 amps (excessive drain), requiring battery replacement. Subsequently, alternator failed and was replaced; oil was found everywhere after alternator replacement, source unknown.
When: One complaint occurred mid-intersection while vehicle was operational.
Symptoms owners cite: Battery saver mode activates unexpectedly; Dashboard lights flicker and turn off; Vehicle will not start; Battery drain (89 amps reported); Oil found in engine bay after alternator replacement
Repairs/costs cited: Battery replacement performed. Alternator replacement performed; oil discovered everywhere after replacement with unknown source.
Stability Control and Antilock Brake System Malfunction
Stability control system and antilock braking system stop functioning during winter/snowy conditions. Owner reports brakes become unresponsive, causing vehicle to run through red lights. Dealership blamed snow/weather rather than investigating underlying defect. Issue has persisted since December 2018 on early-purchase vehicle.
When: During snowy/winter driving conditions; reported since December 2018 on vehicle with 34,500 miles.
Symptoms owners cite: Stability control system disengages; Antilock braking system disengages; Brakes become ineffective or unresponsive; Vehicle ran through red light
Recalls/TSBs owners mention: Dealership blamed snow rather than investigating root cause. GMC has not provided solution or recall; owner reports being told nothing would be done.
Engine Speed / RPM and Temperature Gauge Malfunction
RPM gauge fails to register or display while vehicle is moving. Temperature gauge shows 0 degrees or flatlines. Check engine light illuminates. Multiple issues occur simultaneously: no RPM reading, no coolant temp reading, reduced steering, no A/C, stability control issues. Vehicle experiences electrical cascade failures where multiple systems fail at once.
When: While driving on highway at approximately 40 mph in one case; occurs when cruise control and A/C used simultaneously in another.
Symptoms owners cite: RPM gauge reads zero while vehicle moving at 40 mph; Temperature gauge reads 0 degrees or flatlines; Check engine light illuminates; Engine coolant temp reading of 0 degrees
Codes mentioned: P0128
Infotainment System Glitching
Infotainment system experiences independent activation and glitching, performing unintended functions that distract the driver. System was replaced upon vehicle purchase due to this failure, but recently recurred.
When: While driving at various speeds; recurred after system replacement.
Symptoms owners cite: Infotainment system glitches and performs independent functions; System distracts driver with unintended activation
Repairs/costs cited: Infotainment system was replaced by previous owner/at purchase.
Transmission Slipping and Shifting Issues
Transmission experiences slipping and inability to shift gears during operation. One owner reports transmission behaving roughly and refusing to shift to next gear during highway driving, creating highway safety hazard when combined with steering issues.
When: During highway driving; one owner reports this as ongoing issue over extended period.
Symptoms owners cite: Transmission slips during operation; Vehicle drives roughly; Inability to shift to next gear; Transmission temp flatlines
Unintended Acceleration and Brake Failure
Vehicle experienced erratic speed increase on highway with simultaneous brake failure, resulting in loss of steering control and multi-vehicle accident with injuries. Separate complaint describes vehicle increasing speed to uncontrollable level while brakes became ineffective.
When: While driving on highway.
Symptoms owners cite: Vehicle erratically increased speed without driver input; Brakes became ineffective or non-functional; Loss of steering control; Unable to regain vehicle control
Synthesized from 24 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
The warning light for a steering assist needs service came on the dash. The dealer had a code (po128) that pertained to a bad thermostat and coolant temp. sensor. The steering assist could have failed, along with possible engine damage. The dealer replaced the thermostat and the coolant temp sensor. Their were no police or insurance reports needed.
Had steering trouble with your 2018 GMC Acadia?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the steering problem on the 2018 GMC Acadia?
It's a meaningful issue. 24 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $700.
At what mileage does the steering typically fail?
Based on the 24 complaints filed, steering issues most often appear around 54,700 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $700 for steering repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to steering?
No active recalls currently cover steering issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2018/GMC/Acadia.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.