Yukon hesitation

[gnyzio]

My 2018 Yukon has the 5.3 V8 and 6 speed transmission. While driving on the highway and the engine begins to labor as it starts climbing a hill it feels like the engine is skipping or hesitating in 6th gear. As I press on the gas to get it to downshift into 5th gear I feel the same thing. It does not throw any fault codes or check engine lights so I suspect it is the transmission not the engine. Has anyone experienced this?
Guy

 

[Doubeleive]

My 2018 Yukon has the 5.3 V8 and 6 speed transmission. While driving on the highway and the engine begins to labor as it starts climbing a hill it feels like the engine is skipping or hesitating in 6th gear. As I press on the gas to get it to downshift into 5th gear I feel the same thing. It does not throw any fault codes or check engine lights so I suspect it is the transmission not the engine. Has anyone experienced this?
Guy

mileage?
maintenance history?
if there has been none or next to none then, try cleaning the intake, new air filter, plugs & wires, injector cleaner.
if all of that is current then maybe start monitoring the fuel pressure, check if cat's are clogged.
if it is strictly transmission related then it's time to start saving up for a rebuild

 

[gnyzio]

I bought it this past July with 87K miles. I replaced the air filter, plugs, wires, pcv valve, cleaned the intake and mass air flow sensor and treated with fuel injector cleaner on three separate occasions (Techron and seafoam). I even tried 93 octane fuel. I havnt checked fuel pressure yet or clogged catalytic (but I believe that would throw a fault code). I was smart enough to buy an extended service plan through AAA just in case I did need any major repairs.

 

[Doubeleive]

I bought it this past July with 87K miles. I replaced the air filter, plugs, wires, pcv valve, cleaned the intake and mass air flow sensor and treated with fuel injector cleaner on three separate occasions (Techron and seafoam). I even tried 93 octane fuel. I havnt checked fuel pressure yet or clogged catalytic (but I believe that would throw a fault code). I was smart enough to buy an extended service plan through AAA just in case I did need any major repairs.

at only 87k it shouldn't be a clogged cat, I would check fuel pressure and see what it is showing when the problem occurs, this means with a manual gauge propped up thru the hood so you can see it thru the window. also I would use a scanner and see what the maf is reporting and look at fuel trims.
if it is not the transmission then likely it is air/fuel related ( my best guess anyway) bad maf, throttle body, low fuel pressure or something. If has power around town and chokes out on a climb.
87k is a bit early for transmission problems, but not impossible the 6l80's "can" typically start having problems around 120k with the torque converter which is the weak spot
sounds like you have been maintaining it.
i would report back with your readings and I can tag some of the other members and maybe we can help get to the bottom of this.

 

[gnyzio]

So I had the owner of a very reputable transmission shop take it for a test drive and he confirmed that the torque converter is starting to fail. He said he does a lot of repairs on these GM 6 speeds for the same problem, very common. When he does this repair he also replaces several other components with better quality than the original GM and I shouldn't have anymore issues with it. $4500 - $5500 bucks though! Good thing I bought the extended service plan.

 

[Doubeleive]

So I had the owner of a very reputable transmission shop take it for a test drive and he confirmed that the torque converter is starting to fail. He said he does a lot of repairs on these GM 6 speeds for the same problem, very common. When he does this repair he also replaces several other components with better quality than the original GM and I shouldn't have anymore issues with it. $4500 - $5500 bucks though! Good thing I bought the extended service plan.

good luck, he's going to have to show evidence of the failure to the insurance company (they send adjusters out to verify). there is a list of reasons for them to deny coverage, keep your fingers crossed