2018 GMC Yukon Problems

What owners report

Owners of the 2018 GMC Yukon report two large themes: engine failures tied to lifters, camshafts, and pushrods, and transmission problems that show up as harsh or delayed shifting, slipping, shudder, and in some cases complete failure. A smaller but consistent set of complaints covers the power steering going out, the brake vacuum pump reducing power assist, the air conditioning condenser leaking, and the Magnetic Ride front shocks leaking at fairly low mileage. Many of these show up well past 50,000 miles, though engine and transmission reports also appear in the 40,000-80,000 mile range.

1. 1
   Engine

   Engine lifter/camshaft failure and engine replacement

   • 15 complaints (21%)
   • typically at 7.5 yrs old
   • filed 2024–2026

   Owners describe a ticking, knocking, or rumbling noise from the engine, sometimes with reduced power, misfires, or a sudden shutdown while driving. Several complaints state that after inspection the dealer or shop found failed lifters, a damaged camshaft or bent pushrods, and in a number of cases recommended a complete engine replacement. Some owners mention oil consumption or oil-fouled spark plugs discovered alongside the damage, and several note the vehicle was not included in a later recall covering similar failures on newer model years. Reports cluster between roughly 40,000 and 110,000 miles, with several in the 48,000-81,000 mile range and no warning light beforehand in some cases.

   2 related service bulletins

   What to check: Listen for ticking or knocking at cold start and on light acceleration, check the oil level and smell for fuel dilution, and ask for service records showing any lifter, camshaft, or engine replacement work. A service bulletin describes replacing the camshaft actuator magnet for engine shudder, and another covers intake manifold replacement when an engine is replaced after internal damage.

   2 excerpts from owner complaints in NHTSA records

   “As we were driving, without warning, the engine started to rumble and clank. We had to pull off the road in a neighborhood and have it towed to the dealership. Thankfully, we were driving on side/neighborhood roads at the time. If this would have happened on the highway it could have been very dangerous. They'll dealership said it was unsolvable and we needed to purchase an entirely new engine.”

   NHTSA complaint #11645755, filed 2025-03

   “NHTSA's recall number 25V-274. This vehicle should fall under this recall it happed to the this motor at 58k miles and I had to put a whole motor in it at 58k miles in 2022. The Yukon Denali has the L87 V8. I bought the new motor threw GM so it should be tied to this vin number”

   NHTSA complaint #11657717, filed 2025-04
2. 2
   Transmission and drivetrain

   Transmission shudder, harsh shifting, slipping, or failure

   • 13 complaints (19%)
   • median 102,500 mi at 7.6 yrs old (2 state mileage, few)
   • filed 2022–2026

   Complaints describe hesitation and sluggish acceleration, shuddering between about 40 and 50 mph, clunking or jerking on deceleration, delayed engagement, and occasional loss of power or a shift into neutral while driving. Some owners report a 'Transmission Hot - Idle Engine' message, and dealers have tried fluid changes, thermostat and water pump replacement, TCM reprogramming, and in some cases full transmission or valve body replacement. Several owners say the symptoms returned after the first repair attempt. Mostly reported from about 50,000 miles upward, with many around 80,000-105,000 miles; some note the behavior was present from early ownership.

   What to check: Drive it long enough to feel upshifts and downshifts at 40-50 mph and during a coast-down, and ask whether the transmission fluid has been serviced or the TCM reprogrammed. Ask for any transmission or valve body replacement history.

   2 excerpts from owner complaints in NHTSA records

   “I purchased my used GMC YUKON from a used car dealership 3/28/26. I signed the papers for the agreement while I was driving the vechicle home I lost power and it wouldn't go forward with gas applied. The check engine light came on, I pulled the suv over and it was towed. The code that popped up 0700 and 02723 both codes having to do with the transmission.”

   NHTSA complaint #11727838, filed 2026-03

   “My 2018 GMC Yukon SLE has a Transmission Failure and a engine oil coolant failure. The issues occurred while driving when the vehicle had to go into limp status to prevent the transmission from complete failure. I have taken the vehicle to the dealership 2x and they changed the fluid once and replaced the thermostat the second time. …”

   NHTSA complaint #11670575, filed 2025-07
3. 3
   Other or unknown

   Air conditioning condenser leak and loss of cooling

   • 17 complaints (24%)
   • median 35,574 mi at 3.3 yrs old (6 state mileage, few)
   • filed 2018–2026

   Owners report the air conditioning intermittently or completely failing to cool, traced by dealers to a leaking condenser or coolant line, with one repair covered under warranty and others not. Several complaints note that a special coverage program for the same condenser leak covered earlier model years but not this one, and that the shield added as a fix did not stop the leak. Mostly reported between about 40,000 and 70,000 miles, often noticed as cooling fading in warm weather.

   1 related service bulletin

   What to check: Run the A/C on maximum for several minutes at idle and check for weak cooling, and ask whether the condenser or refrigerant lines have been replaced. A diagnostic bulletin exists for A/C concerns.

   2 excerpts from owner complaints in NHTSA records

   “GM already has extended the warrant for faulty AC Condensers model years 2015-2017. This model 2018 experiences the same exact condenser leak as the 2015-2017 models. In fact special coverage adjustment 17336 which omits the 2018 model has the same failure. This warranty should be extended into 2018 as well.”

   NHTSA complaint #11523225, filed 2023-05

   “Air conditioner condenser faulty and had to repaired. Premium Ride Shocks faulty and had to be repaired. Lifters and bent pushrod faulty and had to be repaired. Vehicle currently has approximately 70,000 miles. These are all known issues by GM and very expensive to fix and no recalls.”

   NHTSA complaint #11700880, filed 2025-11

Buying note. Have a pre-purchase inspection focus on engine noise and oil consumption, transmission behavior at 40-60 mph, brake pedal effort at low speed, and A/C output, since those are the areas most often described in complaints. Ask for service records and confirm whether the brake vacuum pump recall campaigns have been completed on the specific vehicle.

Summary written with AI from a sample of 57 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.