2020 GMC Yukon XL: engine knocking or ticking

Filed Jul 23, 2026 · TX

The vehicle has an unpredictable and random tendency to hesitate when the gas is pressed. This has been happening at some level since the vehicle was new. The dealership service department was never able to get the vehicle to do what I was concerned about, so they never helped resolve the issue. Now that it is out of warranty, the issue is getting worse. It is to the point that I believe it is unsafe for anyone but me to drive it. I have to make sure that when I turn onto a new road, that there is absolutely noone coming because I cannot depend on my vehicle to accelerate quickly enough, even at a normal rate. It may lag and take its time speeding up, or it may accelerate normally with no issues. I stopped going to the dealership for oil changes and checking the issue because they no longer give loaner vehicles and they take a minimum of three hours for an oil change. So I recently took it to my trusted mechanic. He replaced the knock sensors, which helped slightly. He could still detect issues, but was concerned it would require a whole new engine built to bypass the DFM system and repair the cams and lifters. So I nw have to drive a vehicle that needs $20,000 worth of repair, has the potential to be dangerous or leave me broken down on the side of the road. It has 106,000 miles and I still owe $12,000 on it. From my research, I understand that this is a known issue and that there are several lawsuits regarding the issue. That does not help the average person who doesn’t care about a lawsuit, but is justifying st trying to live their average life with a dependable vehicle. Please help!

Filed Jul 12, 2026 · Engine · TN

My family drove from [XXX] to [XXX]. Upon arrival check engine light came on, we proceeded to a local shop, by the time we arrive check engine light was flashing and engine was knocking and was clearly malfunctioning. Shop owner recommended we transport the vehicle back home as service shops in the area were experiencing high volume and parts shortages. We had vehicle towed to a local shop in [XXX]. The engine is giving diagnostic codes P0300, P050D, [XXX] with internal knocking and tapping. Vehicle has been kept current on all oil changes and has no external leaks. GMC wants at least $12,000 to replace the engine. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Mar 4, 2026 · Engine · 113,997 miles · TX

The contact owns a 2020 GMC Yukon XL. The contact stated that while driving at 35 MPH, there was an abnormally loud ticking sound coming from the vehicle. The driver was able to pull over safely. There were no warning lights illuminated. The vehicle was towed to an independent mechanic who determined that the lifter was stuck in the bore, and there was a misfire in cylinder #7 due to a stuck camshaft. The local dealer was not contacted. The manufacturer was not notified of the failure. The failure mileage was approximately 113,997.

Filed Feb 22, 2026 · Engine · CO

My 2020 GMC Yukon XL Denali 6.2L with 59,000 miles developed a ticking noise and slight power loss diagnosed by three different garages as a "collapsed lifter" on #4 cylinder. It's one of the AFM/DoD cylinders that shuts down to save fuel. $8,000 repair estimate, or $12,000 if the failed lifter damaged the camshaft. All three garages said "we see a lot of these." Internet forums are loaded with lifter problems on this engine: specifically AFM/DoD lifters. Safety is not affected. Noise/diagnosis reproduced by three independent garages. Has not been inspected by mfg, police, or insurance rep. No warning lamps or messages, no ODB2 "codes" found by garages. Seven months ago the water pump exploded on Interstate 70, putting us at serious risk. Now this lifter trouble at 59,000 miles. Both should have been covered by the 60,000 mile powertrain warranty, but I'm beyond the 5-year limit.

Filed Jan 4, 2026 · Engine · KY

Knocking noise from engine-no check engine light initially. Next time it was started knocking was still present and the check engine light was on. Contacted Champion Chevrolet in LaGrange KY. Dealership diagnosed problem (Code P0308 - Cylinder 8 misfire). Compression test on Cylinder 8 failed. Removed valve cover and confirmed loud tick in the rocker shaft and worn camshaft lobes. Was told I would need a new engine and that repairing the existing engine was not cost effective. So, $22,722.14 later, i have a new engine in my 2020 GMC Yukon and have the original engine (core charge) in my shop in case it is needed for evaluation to help determine if the GM recall should be expanded to 2020 model year (and others not covered by the current recall).

Filed Jun 5, 2023 · Electrical, Engine · CA

Pressed the air condition button and engine turned off while driving. Vehicle engine knocking and engine shaking. Will not go over 30 miles an hour Take it to the dealership and all they say is it's the air filter. Engine light turns on Traction control light stays on Warning of decrease engine speed Engine not shifting properly High rpm's Dealer says there's nothing wrong