2018 GMC Yukon XL Problems

What owners report

Owners of this model year most often write about engine failures tied to lifters or camshafts, often with knocking, stalling, or little warning. Transmission slipping, jerking, or unexpected shifts are also reported, along with brake pedals that become hard to press and air conditioning leaks from the condenser or rear lines. Where mileage is given, the engine and transmission reports mostly fall between about 60,000 and 150,000 miles.

1. 1
   Engine

   Engine lifter or camshaft failure, knock or stall

   • 13 complaints (23%)
   • median 100,500 mi at 7.9 yrs old (2 state mileage, few)
   • filed 2023–2026

   Owners describe engine failures involving lifters, camshafts, or knocking that began with a ticking noise, a flashing check-engine light, or a loss of power. Some engines stopped while driving, and some owners say there was little or no warning light before the failure. Dealers or independent shops reportedly found damaged lifters or camshafts, and some owners were quoted large repair estimates or had the engine replaced or rebuilt. Where mileage is given, it ranges from about 60,000 to 131,000 miles, and some reports name the 6.2-liter V8.

   1 related service bulletin

   What to check: Ask the seller or dealer for any lifter, camshaft, or engine repair records, and check the VIN for open recalls or service campaigns. During a test drive, listen for ticking or knocking, and check for flashing check-engine lights or oil pressure warnings.

   2 excerpts from owner complaints in NHTSA records

   “2018 Yukon Denali engine failed June 2024 due to the lifter being bent. The dealership Richey Cadillac in Daytona Beach estimated the repairs at $18,862 and were going to have my vehicle for months. I took it to my mechanic who rebuilt the engine for $7181 in 30 days. My safety was placed at risk because while driving I had to pull over since I had no control with the engine failure. There were no messages prior to the failure.”

   NHTSA complaint #11660917, filed 2025-05

   “Engine Valve Lifter for cylinder 3 had failed and Camshaft lobes damaged. Error codes of P0300 and P0303. Vehicle had 67,049 miles when I brought it in to be repaired at Park GMC in Greenville, SC on 12/28/2022. GMC has the lifters (they replaced all 8) and the camshaft. Failure happened while on I40 in the Smokey mountains at night while driving back from Dollywood with my family. Engine produced a gassey sputtering sound and I lost some power but only noticeable under acceleration. …”

   NHTSA complaint #11539682, filed 2023-08
2. 2
   Transmission and drivetrain

   Transmission slips, jerks, or shifts on its own

   • 11 complaints (20%)
   • median 40,000 mi at 3.5 yrs old (5 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2019–2026

   Owners describe the transmission slipping, jerking, or lagging, with sudden loss of power or surging on the highway, and some report the vehicle rolling backward on a hill or moving in reverse while in drive. One says the gear selector slipped back into neutral after a restart, and another says the vehicle engaged reverse on its own after the engine was turned off. Some say a dealer or service center confirmed the problem or called it a known issue, and several describe transmission rebuilds or replacements at high cost. Where mileage is given, it ranges from about 102,000 to 148,000 miles; the descriptions include highway, uphill, and low-speed driving.

   What to check: On a test drive, check for slipping, jerking, or delayed engagement when shifting from park to drive and when pulling away on a hill, and confirm the gear selector stays in position. Ask the seller for transmission repair or rebuild records, and check the VIN for open recalls or service campaigns, since some owners say they were told the problem is common.

   2 excerpts from owner complaints in NHTSA records

   “When I let go of the brake the vehicle accelerates on its own. It's a scary feeling, I feel like don't have control of the vehicle. Another problem that I have is that I can not put my vehicle in gear right away when I turn on the engine. Another problem that I have is rattling sound and vibration on the gas pedal when I accelerate.”

   NHTSA complaint #11398614, filed 2021-03, 5,000 miles

   “2018 Yukon XL: Safety of family put at risk over faulty transmission. Vehicle used to transport children many times daily. Transmission began slipping with slight lagging. Vehicle assessed by independent service center and we as customers told this is a common issue with GMC vehicles of this year. Service center was able to reproduce and confirm the issue. Total to rebuild entire transmission was $7,377.33. Total transmission failure. Entire transmission had to be replaced at tremendous expense to our family. …”

   NHTSA complaint #11643967, filed 2025-02
3. 3
   Brakes

   Brake pedal hard to press or brakes lose power

   • 14 complaints (25%)
   • median 37,000 mi at 2.4 yrs old (4 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2019–2026

   Owners describe brake pedals that become very hard to press, or brakes that lose power and slow the car less than expected, often with a brake assist warning on the dash. Some link it to a seized or failing vacuum pump, and one says the pump was replaced and the same problem returned within about a week. Another describes the brakes feeling applied and then failing completely while driving, and one owner cites a GM special coverage adjustment for brake vacuum pump failure with similar symptoms. Where mileage is given, it is about 31,000 to 40,000 miles; the descriptions include stop-and-go traffic, parking lots, and city streets at about 30 mph.

   What to check: Check the brake assist warning and the pedal feel at startup and during slow stops, and ask the seller whether the brake vacuum pump has been replaced or any brake assist repairs were done. Ask the dealer to check for stored brake assist codes and whether any GM coverage or special adjustment applies to the VIN.

   2 excerpts from owner complaints in NHTSA records

   “First time was in reverse in our drive way. Then pulling into parking lot, brakes were hard to push with pulsing pedal and warning message on dash, check brake assist. We got vehicle stopped, hard brake pedal, without hitting anyone. This happened six times on 03-05-2020. This occurs at slow speed in stop and go traffic or in a parking lot, not a good feeling. It feel like the vacuum pump can not supply enough vacuum to operate brake booster. We have only owned vehicle for about three weeks. The vehicle is not safe to drive in this condition.”

   NHTSA complaint #11317150, filed 2020-03, 40,000 miles

   “I was driving straight on a city street at about 30 miles per hour and a car was coming over on me so I had to hit the brakes hard so that we would not collide. My car slowed down but did not stop. I was on the brakes hard, but my car only slowed, it did not stop. The other car hit me. After we exchanged information I drove off and I kept stopping to see if the brakes were working, but they worked every time after that. I was telling my sister what happened and she mentioned a friend of hers had a Gmc that was recalled due to faulty brakes. …”

   NHTSA complaint #11311821, filed 2020-02, 31,400 miles
4. 4
   Other or unknown

   AC condenser or line leaks refrigerant

   • 6 complaints (11%)
   • median 58,000 mi at 3.5 yrs old (3 state mileage, few)
   • filed 2020–2025

   Owners describe warm air from the vents, and dealers or independent shops finding a leak in the condenser, a rear air conditioning line, or the rear evaporator coil. Some say they paid a diagnostic fee before the leak was found, and one says the manufacturer would not warranty the part because it was reportedly installed incorrectly. The complaints say a dealer service representative reported the condenser leak happens often on 2014 and newer models, and one says the VIN was not under recall for the failure. Where mileage is given, it ranges from about 21,000 to 73,000 miles; one complaint describes the problem appearing when the air conditioning was first used in spring.

   What to check: Ask for the condenser, rear air conditioning line, and rear evaporator coil to be checked for leaks, not just recharged, and run the air conditioning at idle and on the highway during the test drive. Ask whether a diagnostic fee applies and whether the repair is covered under warranty before agreeing to the work.

   2 excerpts from owner complaints in NHTSA records

   “It’s starting to warm up now that winter is behind us, so when we recently drove our 2018 Yukon XL, we turned on the air conditioning. Unfortunately, only warm air came out of the vents. We made an appointment and took the Yukon to the GMC dealer. We paid over $160 for their diagnostic fee (complete rip off), and they were immediately able to see that there was a leak in the AC condenser. …”

   NHTSA complaint #11460934, filed 2022-04

   “The air-conditioning (A/C) unit in my 2018 GMC Yukon XL (my vehicle) is not blowing as cold as usual. The dealership (Westpoint GMC) where I purchased my vehicle says their A/C department is backed-up and that I would need to leave my vehicle with them for 2 to 3 days to run diagnostics. I took my vehicle to another General Motors dealership instead, Westside Chevy, and their A/C department or technicians state that my vehicle has a leak in the rear evaporator coil after running their leak detection tests. …”

   NHTSA complaint #11547838, filed 2023-10
5. 5
   Seat belts

   Rear seat belt retractors fail to lock or break

   • 5 complaints (9%)
   • median 26,755 mi at 2.0 yrs old (1 states mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2019–2026

   Owners describe rear seat belt retractors that do not lock or retract properly, with belts rubbing inside the body, snapping, or staying loose. One says a child seat belt did not hold steady in a crash at about 20 mph with no warning light, and another says a child seat tipped because the belts did not lock. Some say a belt was replaced after it snapped, and another was quoted a repair cost in the thousands. Where mileage is given, it is about 27,000 miles; most descriptions do not list mileage.

   Recall 18V673000

   What to check: Check each rear seat belt by pulling it fully out and letting it retract, and confirm it locks in place for a child seat. Ask whether recall 18V673000 has been completed for the VIN and whether the second and third row retractors were inspected.

   2 excerpts from owner complaints in NHTSA records

   “Driver seat automatically adjusts while driving particularly when I accelerate from a red light or stop sign. This causes me to not reach the peddles.I have to pull over and reset my seat. Has been doing this for two days.My vehicle is not equipped with the automatic memory seat. My two rear seatbelts in the middle row are always lose they do not retract. This has been going on for a couple of months.”

   NHTSA complaint #11584742, filed 2024-04

   “Both second row seatbelt retractors have had issues retracting. We had them checked today while our car was in for other issues. Both seatbelt retractors are broken and need replacing ($1600). Without replacing them, the passengers using those seats would be at grave risk in an accident. We are the original owners of the vehicle, our young children are fastened in their booster seats with parental help. There has been no extreme wear and tear or any abuse to the seatbelts.”

   NHTSA complaint #11629981, filed 2024-12

Buying note. For a used purchase, check the VIN for open recalls and service campaigns, and ask for engine, transmission, and brake repair records, since these were the most common areas in the complaints. On a test drive, listen for ticking or knocking, check for slipping or jerking when shifting, and confirm the brake pedal stays firm.

Summary written with AI from a sample of 53 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.