STELLAR Fuel Milage

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CTown Duramax

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33.6 mpg on a 173 mile trip from sea level to 1,700 ft back down to sea level, up and down terrain, cruise control set to 65mph and drove 65mph the whole way, never below except to stop, speeding up to 72mph downhill, sunny, dry 37 deg F above freezing whole way. I was at 34mpg before getting into the city. Best 50 mile average this trip was 39.3. If I drive this route the "normal" way - ie, 77mph +/- keeping up with traffic, the milage is the EPA reported 26-27mpg. City commuting partial in town expressways gets 20-22 mpg. Sitting in traffic stop and go gets 14mpg. This engine is amazing, still breaking in at almost 4,000 miles. I'll update my review at 5,000 miles. I'm having a great ownership experience so far.

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Stbentoak

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The bast way to get 30 mpg is to keep it a 65 ish MPH. Unfortunately, you will get run over on most interstates driving this speed. I get appx 26-27 MPG but we are running 85 just to keep up. I've been passed by Kia Soul's running flat out at 100 MPH on open stretches of FL-GA highways...
 

R32driver

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The bast way to get 30 mpg is to keep it a 65 ish MPH. Unfortunately, you will get run over on most interstates driving this speed. I get appx 26-27 MPG but we are running 85 just to keep up. I've been passed by Kia Soul's running flat out at 100 MPH on open stretches of FL-GA highways...
It's just amazing how incredibly fast people drive these days. I'm usually the slowest guy on the road and get passed by all makes and models, but I'm usually not in a big hurry to get anywhere. Maybe rising gas prices will slow people down? Doubtful but wishful thinking at least
 

Pro299

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It's just amazing how incredibly fast people drive these days. I'm usually the slowest guy on the road and get passed by all makes and models, but I'm usually not in a big hurry to get anywhere. Maybe rising gas prices will slow people down? Doubtful but wishful thinking at least
Ha. I agree. Unless we're running late, I generally cruise interstates at 77 or so, 80 tops. Feels like I'm poking along as I'm passed by nine out of 10 vehicles around me. And not by just a little. Most must be in the 85-90 range. Almost reminds me of the years we lived in Germany. All I know is that if I drove like that these days, my license would be toast. As for mileage, most of ours is I-65 in AL, TN, and KY. Nothing but hills. Usually get 25-26 MPG.
 
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CTown Duramax

CTown Duramax

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It's just amazing how incredibly fast people drive these days. I'm usually the slowest guy on the road and get passed by all makes and models, but I'm usually not in a big hurry to get anywhere. Maybe rising gas prices will slow people down? Doubtful but wishful thinking at least
I'd say drivers on the interstates here in Mass have been going five to ten mph slower since gas reached about $4.50 a gallon. The unofficial speed limit here is 80 mph. Troopers will stop you if you go over 80. I usually try to keep up with traffic. Then I get about 26-28, same as my last model V-6 Impala. Right now, with drivers trying to save gas, going 65-72 mph is reasonable. I've noticed in states like FL and TN that the unofficial speed limit must be 85 or even 90.
 

Stbentoak

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At 85, troopers won't even look at you in Fl and TN/KY. They are too busy going accident to accident. I75 and I95 are not for the timid...You'll get run over doing the speed limit...
 

RaptorJet31

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Ya the duramax jr is pretty impressive. We drove up to OR and picked it up 2 weeks ago, averaged 27-29 almost the whole way home. Pretty crazy for a 6k lb suv. Hoping to go fish this week, I really want to see how it tows my boat in the mountains here and also to see if there is any exhaust brake while actually towing. It is the one thing I miss coming from my 20' silverado 2500 that truck towed beautifully but had no reason for it after selling my trailer. The Ex brake on the 2500's works great even when not towing. So far very happy and so is my family.
 

StephenPT

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Ya the duramax jr is pretty impressive. We drove up to OR and picked it up 2 weeks ago, averaged 27-29 almost the whole way home. Pretty crazy for a 6k lb suv. Hoping to go fish this week, I really want to see how it tows my boat in the mountains here and also to see if there is any exhaust brake while actually towing. It is the one thing I miss coming from my 20' silverado 2500 that truck towed beautifully but had no reason for it after selling my trailer. The Ex brake on the 2500's works great even when not towing. So far very happy and so is my family.
From what I've read, when you are in tow/haul mode, the exhaust brake will activate when going down a grade.

Also, where at in OR did you pick up your Suburban?
 

Geotrash

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At 85, troopers won't even look at you in Fl and TN/KY. They are too busy going accident to accident. I75 and I95 are not for the timid...You'll get run over doing the speed limit...
Precisely why we have 2 XL Denali's. I-95 between Richmond and Washington, and I-81 in the western part of the state are killers. When we brave these corridors, I want as much height and metal around us as I can get.
 

RaptorJet31

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I bought it
From what I've read, when you are in tow/haul mode, the exhaust brake will activate when going down a grade.

Also, where at in OR did you pick up your Suburban?
I bought at Ashland chevy, everyone around here in northern CA were 5k to 10k over msrp haha I saw one on chevy inventory I liked and called them. As far as towing I towed my boat yesterday for the first time. I have some very steep mountains to get up and come down at the lake by my house. Boat and trailer with all my gear is roughly 4500# and the suburban/duramax towed up those steep hills no problem. It's definitely not like my 2500 trucks but it had no issues at all getting up those steep grades, I was actually surprised. The exhaust did not do much tho, I see when I click it in tow mode it says "exhaust brake ON" but I honestly could not feel it much, I might be used to HD trucks, it wants to use the engine more than the exhaust brake, so I have to ride my brakes down the mountains which sort of sucks, but it is what it is.
 

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altona

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My first refuel on my 2022 Yukon Denali 4x4. 15.5 gallons, 347 miles driven, DIC said 23.0 mpg, hand calculation was 22.6, but not sure dealer filled it all the way full on delivery. There was a lot of short trips, and idling while learning and setting controls on this thing. DIC also said we only averaged 29 mph. Did see 29.8 mpg on the trip down I75 which was 25 miles long.
 
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CTown Duramax

CTown Duramax

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This is a wonder engine. Just got 35.1mpg going east to west on the same route with cruise control set at 65mph. Will post pic tomorrow and I'll do the math when I fill up to check on the DIC. I keep my tires at 37psi cold, so that helps mpg a little, handles better too.

I don't mind going slower at $5.00/gal. After I'm through experimenting, I'll probably go back to my usual 77mph/28mpg. Interesting to learn about higher speeds in other states. Here in People' Republic of Massachusetts, 95mph will get you jailed. Sometimes you can get away with a little over 80mph when everyone's going fast on a crowded road. NY is 5mph lower threshold. Sounds like FL gives drivers more freedom.
 
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tights24

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Yeah, I live just north of Tampa. You can safely set the cruise on 82-83mph and drive without worrying about passing a trooper. They do have some local yocals on the interstate here and there and they will nab you at those speeds, but the lion share of five-o on the interstates are troopers, and you need to be breaking 85 to be looked at. At least 90% of the time imo.
 

altona

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Driving roughly a 50/50 mix of short around town trips and 60 to 65mph country roads, with only 900 miles total on the Yukon, I hand calculated 26.4 mpg. BTW, that is within .2 of the info ctr readout.
 
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CTown Duramax

CTown Duramax

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You can see the pic first above showing 33.6 for 170 miles, but I did not get a good picture of the read out this time, sorry. I made the return trip from the 65mph/35.1mpg run at normal speeds, cruise set at 75mph, accelerating above that a couple times and still got 30.1 mpg, so I don't need to stick to 65mph to get high fuel milage. Fuel efficiency went up after 4,000 miles. Hand calculation after fill ups confirms accuracy of the DIC read out. This is crazy good fuel consumption.
 

StephenPT

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This thread has me excited to get our Yukon XL Duramax. Here in the Pac-NW, the highest freeway speed limit you'll see is 70mph, often times it drops down to 60mph on sections of I-5. We frequently travel from Portland to Olympia and sometimes I'll do 75mph in the left lane and other times just tag along with the semi-tractors in the RH lane with cruise set at 62mph. The best we can get on that trip is ~25mpg in our Honda Pilot, if I stay in the mid-60's.

Seeing these numbers of mid-30's if you keep your speed in the mid 60's blows my mind. To think that we'll have a bigger rig, tons of cargo space, kids in the 3rd row will feel like they're in a different zip code AND get better fuel mileage than our mid-size SUV? We can't wait!
 

Stbentoak

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If you do any kind of interstate driving and don’t plan on getting mowed over, I don’t think 35 mpg is attainable. The absolute best I ever got was 30.9. And that was being stifled by traffic that kept us around 60 to 65. If you’re going with most flows and you’re running 75 to 80 you’d be lucky to get 30. I’ll do 600 miles a day and average high 20’s, which is still highly respectable in my book As we move with the fastest flow….
 

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