This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
full bulletin at NHTSA ↗2019 GMC Acadia engine problems
moderate Owners of the 2019 GMC Acadia have filed 22 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
22
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2015 Acadia | 4 |
| 2016 Acadia | 4 |
| 2017 Acadia | 22 |
| 2018 Acadia | 7 |
| 2019 Acadia (this page) | 22 |
| 2020 Acadia | 8 |
| 2021 Acadia | 17 |
| 2022 Acadia | 6 |
| 2023 Acadia | 3 |
What stands out
No new NHTSA engine complaint has been filed on this vehicle in over 4 years — the issue may be aging out of the active population.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine 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.
The service bulletin advises the tech of a normal transmission shift condition and the delay in throttle response when the throttle plate is opened rapidly and advises the customer that it is normal for the delay.
full bulletin at NHTSA ↗This service bulletin provides information to dealership personnel for new vehicles with less than 1,000 miles that may not pass California smog inspection or smog inspection in other states.
full bulletin at NHTSA ↗This warranty administration bulletin provides policy information on vehicles outside of a California Emissions State who move to and register their vehicle in a California Emission State may be entitled to the 7 year, 70,000-mile Emission Select State Component Limited Warranty.
full bulletin at NHTSA ↗This service bulletin provides a procedure to add deadener to the batter tray bracket to correct customer concerns of a Service Engine Soon (SES), Reduced Power, Service Brake, Reduced Steering and/or Stabilitrak Message Illuminated on DIC, multiple DTCs.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 2019 GMC Acadia engine cluster centers on a thermostat / water outlet assembly that fails routinely at 72–80k miles, well before typical design life. Owners describe it getting stuck open, causing the temp gauge to read zero, disabling AC and steering assist, and triggering check engine lights. The part costs $1,200–$1,300 to replace, and online forums confirm the failure is widespread across the 3.6L V6 engine platform. Some owners have replaced it twice in 10–18 months. Battery disconnect temporarily resets the fault but it returns within days.
Exhaust problems show up as P0420 (catalyst efficiency) codes linked to front exhaust pipe bracket separation and flex pipe damage at higher mileage. Owners also report loud droning and roaring sounds during acceleration, including one case where a full exhaust system replacement didn't solve it permanently.
Oil-related failures include gasket leaks requiring repair six times in 18 months for one owner, piston ring failure prompting full engine replacement, and one radiator that cracked at the top seam just 500 miles past the warranty edge—the dealership confirmed it was a manufacturing defect but denied coverage anyway.
Transmission and ignition issues include shifters that don't register park, forcing vehicles to stay running, and one case requiring shifter replacement at nearly 40k miles that didn't qualify for warranty coverage.
Same GMC Acadia engine reports on nearby years: 2017 · 2021
Failure modes owners describe
Thermostat / Water Outlet Assembly Failure
Thermostat gets stuck, generally in open state, causing coolant overcooling and triggering multiple downstream fault codes. Owners report loss of AC, steering assist warnings, temp gauge showing zero, and check engine light. Some report the fault clears temporarily after battery disconnect but returns repeatedly. Water outlet assembly (which includes thermostat) is the OEM part; replacement cost cited at ~$1,200–$1,300. Pattern appears at mileage around 72–80k miles, roughly half of expected engine design life.
When: 72,000–80,000 miles; first occurrence reported as early as 1 year into ownership; recurring within 10 months of first replacement
Symptoms owners cite: Thermostat stuck open; Temp gauge reads zero or malfunctions; AC disabled or blowing hot air; Steering Assist reduced / disabled warning message; Check engine light illuminated; Soft code before hard code appears; Engine overcooling
Codes mentioned: P0128 (implied by coolant temp sensor failures), Steering Assist system fault codes (triggered by thermostat sensor failure)
Repairs/costs cited: Water outlet assembly replacement; cost ~$1,200–$1,300 per owners. Online forums note thermostat modules for 3.6L V6 are widely available, indicating systemic awareness. Temporary workaround: disconnect and reconnect battery negative terminal; effect lasts 1–2 days before fault returns.
Recalls/TSBs owners mention: No TSBs, recalls, or warranty coverage cited. Owners report extended warranty does not cover thermostat. No goodwill assistance mentioned in narratives.
Front Exhaust Pipe Bracket Separation & Flex Pipe Damage
Front exhaust pipe bracket snaps, damaging the flex pipe and causing an exhaust leak. Owners report P0420 (Catalyst System Efficiency Below Threshold Bank 1) code as current, history, pending, and permanent. Produces noise, exhaust odor, potential fumes in cabin, and emissions noncompliance. Documented as recurring issue on GM's Lambda-platform vehicles (3.6L V6). GM Special Coverage Adjustment N212356540 covers 2019 Chevrolet Traverse and Buick Enclave for the identical failure but explicitly excludes 2019 GMC Acadia despite mechanical equivalence.
When: ~87,164 miles in early February 2026; one example at approximately 80,000 miles with loud roaring sound
Symptoms owners cite: Check engine light illuminated; Loud roaring or droning sound from engine area; Exhaust leak visible or audible; Potential fumes in cabin; P0420 code persistent; Exhaust system noise or buzzing during acceleration (1500–2000 RPM)
Codes mentioned: P0420 (Catalyst System Efficiency Below Threshold Bank 1), P0128 (coolant temp related, in one case)
Repairs/costs cited: Requires replacement of front exhaust pipe bracket and flex pipe section. Cost not stated by owners. One owner obtained independent diagnostic confirmation; GM then required redundant diagnostic at authorized dealer (additional cost) before denying coverage.
Recalls/TSBs owners mention: GM Special Coverage Adjustment N212356540 (15 years / 150,000 miles) covers identical defect on 2019 Chevrolet Traverse and Buick Enclave but excludes 2019 GMC Acadia. Multiple owner attempts to obtain goodwill, TSB applicability, or coverage denied by GM Executive Resolution.
Radiator Crack at Top Seam
Radiator develops crack along top seam, causing coolant leak. Occurred less than two years after purchase and only 500 miles past the 3-year / 36,000-mile factory warranty expiration. Dealership acknowledged manufacturing defect; GMC declined replacement solely due to mileage overage. No impact damage reported; seam split spontaneously.
When: Under 2 years old; 500 miles past warranty expiration (estimated ~36,500 miles)
Symptoms owners cite: Coolant leak visible on garage floor; Crack visible at top seam of radiator; Leak detected 10 days after last service with no prior issues
Repairs/costs cited: Radiator replacement required. Owner has photos, dealership written acknowledgment of defect, receipt, and the cracked radiator itself. Cost not stated.
Recalls/TSBs owners mention: GMC denied replacement coverage despite dealership and manufacturer acknowledging manufacturing defect, citing 500-mile warranty overage. Owner has open GMC case number and documentation.
Oil Gasket & Plate Leaks
Oil gasket and oil pan gasket failures causing internal oil leaks. One owner reported oil gasket and plate needing replacement at 72,885 miles. Another owner reported six separate oil leak repairs in 18 months with no warning lights to alert driver, creating dangerous condition of potential engine starvation.
When: 72,885 miles; another pattern of repeated failures over 18 months of ownership
Symptoms owners cite: Low oil message displayed (one case); Oil leaks from engine; No warning lights to alert driver of oil loss; Excessive oil consumption
Repairs/costs cited: Oil gasket and plate replacement diagnosed by dealer. Cost not stated. Owner with six repairs in 18 months did not complete repairs at time of complaint.
Recalls/TSBs owners mention: None cited in narratives.
Piston Ring Failure / Excessive Oil Consumption
Engine consuming excessive oil due to failed piston ring. Owner reports burning through oil, check engine light, prior hesitation during acceleration and gear changes. Shop diagnosed need for full engine replacement. Creates dangerous condition of potential engine shutdown while driving.
When: Mileage not stated; prior symptoms (hesitation, gear-change lag) preceded check engine light and oil consumption diagnosis
Symptoms owners cite: Excessive oil consumption; Check engine light illuminated; Hesitation during acceleration; Hesitation during transmission gear changes; Potential coolant failure code (cause unclear)
Repairs/costs cited: Shop recommended full engine replacement. Cost not stated.
Recalls/TSBs owners mention: None cited in narratives.
Transmission Shift Linkage / Shifter Internal Short
Vehicle does not fully shut down; ignition warning light remains on and engine will not turn completely off until multiple restart attempts (averaging 10 start cycles). Diagnosed as internal short in transmission shifter. Shifter and harness replacement required. Occurs at 39,793 miles and denied warranty coverage despite purchase as new vehicle.
When: 39,793 miles
Symptoms owners cite: Vehicle will not turn completely off; Ignition warning light remains illuminated until restart cycle completes; Engine requires multiple restart attempts (average ~10) before shutting down; Yellow light on ignition switch persists
Repairs/costs cited: Transmission shifter and harness replacement. Cost: $903.30. Repair was not covered under factory warranty despite vehicle being new at purchase.
Recalls/TSBs owners mention: Owner has open GMC case number. Requested VIN be added to recall list. No coverage decision stated.
Gear Shift Does Not Recognize Park Position
Vehicle does not recognize shifter position in Park, preventing vehicle shutdown. Engine continues running; vehicle does not fully shut down. Occurs intermittently.
When: Mileage not stated
Symptoms owners cite: Shifter moved to Park but vehicle does not recognize position; Vehicle does not shut down / engine continues running; Requires multiple attempts to achieve park recognition
Repairs/costs cited: No repair details provided.
Recalls/TSBs owners mention: Owner mentions prior recall work was performed but may not have been done correctly.
Exhaust System Noise / Droning Sound
Exhaust or engine produces loud roaring or droning / buzzing sound during takeoff with moderate acceleration (1500–2000 RPM), forward of front passenger area. Sound is more pronounced after exhaust warms up. Dealership replaced entire exhaust system; sound returned after 6 months. On second visit, dealership attempted to loosen and retighten exhaust; sound returned immediately.
When: Recurring; sound returned within 6 months of full exhaust replacement
Symptoms owners cite: Loud roaring or droning / buzzing sound during acceleration at 1500–2000 RPM; Sound originates forward of front passenger area; Sound more pronounced after exhaust is warmed up; Sound persists or returns shortly after attempted repairs
Repairs/costs cited: First repair: full exhaust system replacement by dealer. Sound returned after 6 months. Second repair attempt: loosening and retightening exhaust; sound returned immediately. Cost not stated. Root cause not definitively identified.
Recalls/TSBs owners mention: None cited; only dealer repair attempts noted.
Synthesized from 22 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
I purchased my vehicle brand new off the truck in march of 2020 with zero miles on it. Feb 2021 in negative degree weather, the heat on my vehicle stopped working. I called my local GM dealership and they told me they needed to diagnosed the vehicle. They had kept my vehicle for two weeks trying to diagnose the vehicle. It turned out to be the thermostat. they replaced that part on my vehicle.…
Had engine trouble with your 2019 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 engine problem on the 2019 GMC Acadia?
It's a documented issue but not catastrophic. 22 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Based on the 22 complaints filed, engine issues most often appear around 48,607 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 $3,100 for engine 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 engine?
No active recalls currently cover engine 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/2019/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.