Yukon 07-14 actual mileage

Hello,

I desire to have Denali 6200 XL model and wonder about the actual experience-based mpg (or liter/100km) for it on the highway.

can anyone tell me his numbers on the highway for these cars?

our cheapest fuel here in Jordan is Octane 90. My drive way is highway which is about 200 km, going is up, returning is down and I believe going down saves fuel more than going up for sure.

Talking to people gave me numbers like 12 liters per 100 km but some others insist that it requires 15 liters per 100 km.

Looking forward to your responses!