just did a mileage comparsion on my wifes yukon, started with a full tank and refilled after the trip, all hiway miles and truck has less than 2000 miles on it

cruise set at 75mph and it did 15.6mpg or 18.75mpgcdn..... dic showed 15.5

not bad at all for the new highbread engine at that speed.... did the exact same trip a few days before on my LBZ at the same speed and it did 17mpg or 20.2mpg cdn

i heard westers has some good tunes out for it so my goal is now over 20:D

Im not saying you did bad,but all highway my GMC k2500HD crew cab 4x4 ,8.1 liter will do 13-14mpg at 75-85+mph.I expected a little higher out of it I guess.

I agree with above...you would think they would get more...my '01 8.1 w/mods gets 13.5 all day long on the highway...my wifes '07 Tahoe w/exhaust, intake, and its been lowered2/3" best I've seen is 19mpg...more consistently at 16-17mpg and thats with 12k on the clock. oh yeah and a 4.10 rear.

I wish....My Denali XL can't hit 11 in the city. I've never tried the highway. No need to add to the aggravation.....

But those 07 Denali's sure do rip!:D

My 2007 Yukon XL 2500 2WD does ~15 in general driving & ~12 towing regularly.

just did a mileage comparsion on my wifes yukon, started with a full tank and refilled after the trip, all hiway miles and truck has less than 2000 miles on it

cruise set at 75mph and it did 15.6mpg or 18.75mpgcdn..... dic showed 15.5

not bad at all for the new highbread engine at that speed.... did the exact same trip a few days before on my LBZ at the same speed and it did 17mpg or 20.2mpg cdn

i heard westers has some good tunes out for it so my goal is now over 20:D



Curious if someone knows more about tuning for the 07' Yukons, it was stated that westers has tunes for them, would like to know more about them or if anyone knows of other tunes for them.

Thanks

I wish....My Denali XL can't hit 11 in the city. I've never tried the highway. No need to add to the aggravation.....

my dad has an 07 Denali XL and he is getting amazing mileage! he averaged to the cabin going 65mph 21.1 last weekend (hand calced)... he and i go head to head and he has been beating me lately because he drives slower. They get great mileage when babied, and not waffle-stomping that 6.2 (which is hard to do i know... from experience:cool:)

Good luck!

Im not saying you did bad,but all highway my GMC k2500HD crew cab 4x4 ,8.1 liter will do 13-14mpg at 75-85+mph.I expected a little higher out of it I guess.

Is that modified? 3.73 or 4.10? Ally or ZF6? My CCLB 8.1/ZF6 stock gets about 12 around town and worse on the highway (75 mph).

I would expect better also. My 2000 Suburban with the 5.3L has 120k miles on her and she netted 19mpg (hand calculated) on our last highway trip and that was at 70mph. We normally see 15 to 16 for normal driving. Of course this engine is well broke in.

Is that modified? 3.73 or 4.10? Ally or ZF6? My CCLB 8.1/ZF6 stock gets about 12 around town and worse on the highway (75 mph).

Mine is bone stock,i only get 9-10 around town,but on the highway i get 13-14 easily at 80+mph even. I have 8100/3.73 /Allison,stock size tires 245's. The tires size makes a big difference,larger tires rob mileage,whatever rpms they reduce the engine by are offset by the higher load it takes to turn them,and the taller ride height they run the truck at.

Mine is bone stock,i only get 9-10 around town,but on the highway i get 13-14 easily at 80+mph even. I have 8100/3.73 /Allison,stock size tires 245's. The tires size makes a big difference,larger tires rob mileage,whatever rpms they reduce the engine by are offset by the higher load it takes to turn them,and the taller ride height they run the truck at.

It's got to be the Ally/3.73 vs the ZF6/4.10, cause I have the same 245 tires and everything is stock.

I don't know the 5th gear Ally ratio or the 6th gear ZF6 ratio off hand, but I imagine that times the .37 difference in diff is where its at.