STELLAR Fuel Milage

[CTown Duramax]

Hold on. I am not saying I get 35 mpg all the time. With our mix of bad city traffic and infrequent road trips, we are averaging 20.6 mpg over the last 5k miles. Probably 65% of engine hours are spent in traffic. Milage in bumper to bumper traffic is about 14mpg. It's exactly the same consumption I got with our new model 2015 Impala LT v-6, an efficient sedan. If you drive interstate normally, I think 28-29mpg is attainable after break in, but I do not have the knowledge and experience of Stbentoak. If I am going as fast as I want to go and accelerating as I please, mpg is 26 on the same interstate route. If you were to drive interstate slowly on level ground in warm dry weather all the time, you might stay over 30 mpg. The 35 mpg is not normal b/c run was made under near perfect conditions at night and I was being very light on the gas pedal. My best 50 mile average on that trip was 44.1 mpg obtained coming mostly down hill from an elevation of 1,700 ft to 150 ft. My DIC read out appears to be accurate when I do the calculations at the pump. Tires have cold pressure of 37psi (door sticker says 35psi). Temp betw 40 and 60 degrees, dry weather. Going 80mph drops trip milage 26-27 mpg, still very good. Most northerneast states are not going to let drivers go above 75 or 80 mph, depending on state, so we do drive slower here. I was very impressed recently with the brisk pace of driving in TN.

 

[Larsonxjs]

Im usually getting 28/29 on the highway for a 2 hour ride to Wilmington NC. It all depends on the wind though. On a windy trip I average 25. We are driving a brick with wheels….

 

[BG1988]

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.

View attachment 365583

DEF = more costly still

i would head out to walmart they got it for, BLUEDEF Diesel Exhaust Fluid, 2.5 gal for 15$ buy as much as you can afford before the price skyrockets very sooon they have a shelf life of about 2 years

 

[Stbentoak]

DEF = more costly still

i would head out to walmart they got it for, BLUEDEF Diesel Exhaust Fluid, 2.5 gal for 15$ buy as much as you can afford before the price skyrockets very sooon they have a shelf life of about 2 years

DEF is 11 Bucks at Wal mart where we are for 2.5. DEF is small portion of expense for LM2's unless you are towing. I've spent a grand total of 22.00 for it in 10K miles. Even if it doubles, it's still cheap. Never had a problem getting it, no need to hoard...its not toilet paper...

 

[CTown Duramax]

We have diesel and DEF at about 3/4 of the filling stations in my area.

 

[suterusu]

Best 50 mile average is 31.5mpg going about 75mph. Best 450 mile average is 28.9mpg with a couple heavy stop-go backups on the highway, but cruise still at 75mph.

 

[altona]

Best so far is 33.1 on a 90 mile round trip. Early morning, very little traffic with only 1 quick stop to drop off at airport. Mostly 65 mph with no traffic to run me over, Picture shows a little less after pulling into neighborhood to snap photo.

 

[dbphillips]

Hopefully that 65mph sweet spot correlates to towing mileage...

 

[Stbentoak]

We have diesel and DEF at about 3/4 of the filling stations in my area.

One thing I'm starting to notice is thru the reading I do on other forums, is that people seem to have more codes and issues after filling or using Station pumped DEF vs Pristine 2.5 jugs. That thought may have no basis, but on reading many DEF threads, many have said their last fill before codes popped up was from a bulk dispenser.

 

[Holy Roller]

One thing I'm starting to notice is thru the reading I do on other forums, is that people seem to have more codes and issues after filling or using Station pumped DEF vs Pristine 2.5 jugs. That thought may have no basis, but on reading many DEF threads, many have said their last fill before codes popped up was from a bulk dispenser.

I had this once. And while I don’t think the two were correlated, I never used the pump again. Only the AC Delco DEF sold at the dealer for me.

 

[SC2CO_TAHOE]

I picked up our7 Tahoe LT (DMax) ("The Red Baron") on May 5 and on May 10 started a drive from South Carolina to Colorado. I've included screenshots below of MPG performance along the way. We are traveling with our Dog so we broke the trip up into four segments of approximately 500 miles each. Overall, the truck performed well; there was a definite loss of MPG in the higher speed limit States. The ride was smooth with no notice of cross winds. We are out here until September and then heading back to SC so will be curious to see the performance on teh way back. Enjoy,

Tuscaloosa, AL

Van, Tx

Tucumcari, NM

Colorado

 

[altona]

Rumor has it that you will get slightly better fuel mileage in 2wd instead of auto 4wd

 

[Larsonxjs]

Rumor has it that you will get slightly better fuel mileage in 2wd instead of auto 4wd

Maybe 1 more mpg hwy. The difference is probably added resistance at the transfer case in a 4wd setup.

 

[drmoose]

Rumor has it that you will get slightly better fuel mileage in 2wd instead of auto 4wd

that's good to know/makes sense. I've been keeping ours in 2WD.

 

[altona]

Just finished a 1400 trip up the East coast. 32.1 average, including going only 4 miles in an hour and 10 minutes on I95. Best Range after fill up was showing 740 miles. Speeds were usually set at 67 max at 70. Best 50 mile average was 35.4 mpg. 4wd Denali loaded to the ceiling with cargo and an outdoor storage container on a hitch mounted carrier weighing 250 pounds of fuel and stuff. Yes, it sagged in the rear some.

 

[Stbentoak]

I could possibly get that mileage but at 70 mph we‘d get run over. I avg about 27 at 80-85 and that’s just going with the flow on I 75….

 

[booyaltz]

Chiming in here with my mpg. I've put 3000 miles on my 2022 Diesel Tahoe RST. 27.6mpg total average according to the dash. This is way better than expected. I also had a 2022 5.3L gas Tahoe, and I averaged 17.6 mpg after about 4000 miles before I traded it in. I've driven both the same way - conservatively on mostly flat roads.

 

[Jnull]

Is anyone hand calculating mileage or just going off the dash? If you’ve hand calculated does it come close to what the vehicle says?

 

[Holy Roller]

Chiming in here with my mpg. I've put 3000 miles on my 2022 Diesel Tahoe RST. 27.6mpg total average according to the dash. This is way better than expected. I also had a 2022 5.3L gas Tahoe, and I averaged 17.6 mpg after about 4000 miles before I traded it in. I've driven both the same way - conservatively on mostly flat roads.

Could you share a few words on how the driving experience compares between the 5.3 and 3.0?

 

[booyaltz]

Could you share a few words on how the driving experience compares between the 5.3 and 3.0?

The first thing I noticed was the sound difference. I liked the sound of the v8 more. But after a day I got used to the diesel and it doesn't bother me. The v8 seemed to have a little more power, but the amazing fuel economy of the diesel more than makes up for that. Sometimes the diesel seems to hunt for gears a little, and I don't remember the v8 doing that. I've also had 3 service trips on the diesel vs none on the v8. 1) replaced rear axle due to a leak (this was after only after a few hundred miles I think). 2) headlight sensor malfunction. 3) "service emission system" error. Taking it in to the dealer tomorrow for that. I'm hoping that these 3 issues will be the last problems I have for a long time. Amazing vehicle aside from the aforementioned issues. I get a lot of comments on the looks as well as some "hey you know that's a diesel pump?!" at the gas station. "Yes, it's a diesel."