Actual diesel consumption on 21 duramax Tahoe

[Nima]

Hello
I have a 21 Duramax tahoe with 43k on it.
I feel like my fuel consumption has gone up and I can't tell what's the normal number is
I am getting 14-15liter / 100km combined
I was getting 12liter /100km when I got the truck.
Both numbers seems to be high compare to the GM advertisement
I am wondering what everyone gets in reality.
I feel like the engine runs much louder than when it was new as well but the dealer says everything sounds normal
Please let me know your fuel consumption either in liter or gallon to get a perspective
Thanks

 

[DuraYuk]

Hello
I have a 21 Duramax tahoe with 43k on it.
I feel like my fuel consumption has gone up and I can't tell what's the normal number is
I am getting 14-15liter / 100km combined
I was getting 12liter /100km when I got the truck.
Both numbers seems to be high compare to the GM advertisement
I am wondering what everyone gets in reality.
I feel like the engine runs much louder than when it was new as well but the dealer says everything sounds normal
Please let me know your fuel consumption either in liter or gallon to get a perspective
Thanks

I'm averaging about 20mpg in the city and 28-32 on the highway it's a 2023 yukon.

When my wife drives her number are lower as she has a lead foot. Usually about 16-19mpg in city for her and 28 on the high way.

 

[Pro299]

Last fillup was at 18712 miles. Total gallons 742. So 25.2 MPG overall. Usually 23.5 or so around local, mostly one or two onboard. Interstate depends on terrain. Lots of hills at 75 MPH plus, only about 26 MPG. Flatlands 28-29. I had one tank at 30.1 in south Georgia and north Florida with five passengers plus luggage.

 

[Stbentoak]

Short tripping it ( less than 1 mile per trip ) for a week or so…about 18 mpg.
Normal life 23 mpg….
Head out on the hwy..@ 80 mph 27 mpg… at 65-70 over 30 mpg.
Best ever…34.6 Mpg.
Not a whimper out of it no matter how I drive it.

 

[RK58]

I just travelled from Detroit Mi. area to Tampa Fl. in my 2023 and only filled up twice, once I got down to 1/4 tank and stuck in traffic for 40 minutes along the way. 37 gallons of fuel between the 2 fillups and still half a tank left on my second fill up once I got to Tampa. Very impressive to me, my 6.2's could never get that mileage and I always used 91 octane in them so the price difference per gallon between the two is not that much..

 

[Stbentoak]

I just travelled from Detroit Mi. area to Tampa Fl. in my 2023 and only filled up twice, once I got down to 1/4 tank and stuck in traffic for 40 minutes along the way. 37 gallons of fuel between the 2 fillups and still half a tank left on my second fill up once I got to Tampa. Very impressive to me, my 6.2's could never get that mileage and I always used 91 octane in them so the price difference per gallon between the two is not that much..

I run the same trip basically, Northern IN to Ft Myers and about the same scenario. I made it from Indianapolis to w/in about 50 miles Valdosta GA on one tank. But low fuel light was on coming into the hotel and DTE range said "LO". ....Not ever pushing it like that again.

But super happy that low fuel in this vehicle (IE; 1/4 tank) vs a 6.2 doesn't make me pucker when I see solid red on NAV ahead and nowhere to get off 75.

 

[steiny93]

My not crazy cold numbers are similar to the above.
When it's cold (-30F ambient) I've gotten as low as 20mpg; running straight #1 in 4wd on the interstate with a lot of wind.

 

[Jellyfrosh]

My overall is like 26.5mpg/8.9L/100km but I mostly do highway driving at 65mph/105km/h and I live in a very flat state. My best tank I had was 28.3mpg/8.3l/100km.

 

[OBSSSD]

I average 22 in town and 27 on hwy, 21' Yukon XL