We have had our 05 Yukon 4x4 for a year. I traded in an 03 2500HD CC swb on it. The wife wanted another SUV and I settled on this one due to the gearing. GT5 right in the dash. I'm not really hearing of a lot of GT5 Yukons out there.

Combo city highway it will get 17-19, and towing my 94 K1500 last month it got 14. I did tune it with HP but haven't even put a wide band on it yet. We drove it to Myrtle Beach this past summer from Illinois and it averaged 18 the whole trip. Now don't get me wrong, if you rag on it, it does get poor mpg's

I've had two other GM suv's both Tahoe's and neither did this good. One had 3.42's and the other had 3.73's.

Do I have a freak of a Yukon? or are 4.10's just that few and far between?

 

I'd say rareish... I've never personally seen a factory 4.10, but I've read about a few on here.