New to forum need advise on rough idle

[Ft W crew]

New to forum need advise on rough idle 2011 yukon xl 2500

New to forum and first post.

Just recently, last week bought a CPO 2011 yukon xl 2500 4wd. This truck is awesome, love the power of the 6.0.

I searched the Internet for weeks and had to fly 900 miles and drive it back but the deal I got was worth it.

I have noticed that when I am stopped at a stop light the engine will sometimes shudder, it was really bad on the first tank but now on my third tank it seems to be getting better but still there.

I picked up yukon just outside of DC and drove it back to Florida. I don't know if the colder weather had anything to do with the shudder or the fact it might have some older gas in it from sitting on the lot for almost 60 days. Now on my third tank and being Florida it still does shudder but not as bad.

I know it's under warranty but after researching on the Internet this seems to be a characteristic of this engine or am I mistaking. Any suggestions?

Other than that this truck rocks and looking forward to next weekend when I get to tow my 8000 lb travel trailer.

In case you are curious I replaced my 2007 ford expedition Eddie Bauer 2wd which at best towed the trailer poorly. Even with the 3/4 chassis the yukon rides much smoother and so much more power.

 

[InTruckDesign]

yes it is a characteristic of the motor, mine used to do it, mostly has to do with the tuning from the factory. Even with custom tuning mine still will do it occasionally. As far as towing, you should be fine down in Florida, any hilly terrain and the trans will be downshifting and hunting for the right gear. It should handle the weight, but I felt that the rear is sprung to light, definetly lighter than the 2500 trucks, I added Roadmaster Active Suspension to mine to help control the sag and sway when loaded, also added Rancho 9000xL shocks. I am very pleased with both and the truck is way more stable both when loaded down and unloaded. Good Luck with the Yukon XL overall I think you will be pleased with it.

 

[Parthery]

I have a CPO 2010 Denali with the 6.2....actually found it in SW Florida and drove down from Atlanta to get it.

I have the shudder/stumble at idle as well. Seafoam and a couple tanks of premium helped, but only marginally. My dealer suggested cleaning the throttle body, and doing it has reduced it to where you can just barely feel the stumble, and it doesn't happen all the time now. I'd recommend that.

 

[KMeloney]

Occasional shudder here, too. Cleaning the TB did nothing for me. I'm afraid that it's a characteristic of the engine, as said before.

 

[Ft W crew]

Thanks for the advice, I will try the sea foam and throttle body cleaner. As far as towing the tongue weight is right at 850 lb. the dry weight of trailer is 6424 lbs and I figure I have at least a 1000 lbs of gear. I have used timbrens before on my truck they work great until you hit a speed bump with no weight and you feel it through you spine. If I find that I get a lot of sag or sway I will probably add something. Even stock this xl should tow better than a stock 07 ford expedition el 2wd. I keep you posted

Thanks again.

Btw, I am looking to trade my heat power fold bench for the same buckets, any advice on how to get the word out there?

 

[08grey]

marvel mystery oil and 93 octane solved it for me. I use it at every fill up now. it has not improved mpg at all btw. If you have a cold air intake the throttle body and plate get a little dirtyier faster than with the stock intake, definitly worth a wipe clean.