2021 Tahoe RST Abismal mileage

[JGinLA]

The story I read stated the vehicles were built minus chips and parked nearby until the chips are added.

 

[Quark]

My 2007 Tahoe was getting 14-16mpg, but just upgrade to the 21 RST diesel and it’s light years better in fuel economy which is why I went diesel.

Would the cost per mile; engine option increase, fuel price and added maintenance cost justify choosing the Duramax over the 5.3L?

 

[TahoeFL2017]

If you think the Dealer is playing you, Facebook posts on their page and a BBB complaint will get their attention

Be nice, but sometimes ya gotta get some whoop ass out......

 

[swathdiver]

@1BADI5 It's a 5.3L not a 6.2. My suburban and older Tahoe had similar engines but we experienced much better mileage - about 15mpg. I don't think this truck has the AFM in it like older models. My old trucks would tell us when it was going from 8 cylinder to 4. I've also see the GM lawsuit about that issue on older models but from what I've read that only occurred after several thousand miles. This truck doesn't have that. We are at about 1,500 miles and about 160 hours on the engine. We keep in it in 2WD almost always and don't use any of the performance modes either. I've also noticed that cars computer reporting we are down to 50% of the oil life at only 1,500mi??? We are planning a 1,300 mi trip in June and will be towing about 4k lbs so I need to make sure everything is up to par. I will ask tomorrow about the AFM system. It's a good question.

Seems to me you are doing a lot of city driving and or idling and that is what kills the oil life and gas mileage. Nature of the beast. On the other hand, the motor is new and tight and will get better in time. I had a new V6 once that was really tight, it was slow to rev and got poor mileage until it hit 9K miles and voila! the responsiveness picked up and it got good gas mileage after that for the rest of its days.

 

[Terry Hurlburt]

We own two Yukon Denali’s. A 2014 and a 2018, both with the 6.2 liter engines. The 2014 gets 12-13 mpg in town and the 2018 gets 14-16 in town. I have a pretty heavy foot, so I think others could do better.

 

[Fless]

I don’t

I don’t think that is true. The RVP changes but not the amount of ethanol. If you buy 10% or 15% ethanol fuel you are getting that year round. I have looked into this before. I could be wrong I am not a fuel expert by any means.
https://blog.amsoil.com/the-difference-between-winter-and-summer-blend-gas/

I was speaking more to the content of ethanol in e85. The percentage is reduced in winter.
From the E85 Flex Fuel Specification: https://afdc.energy.gov/fuels/ethanol_e85_specs.html
"E85 sold during colder months often contains lower levels of ethanol to produce the vapor pressure necessary for starting in cold temperatures."

And I was confused by the statement "Maybe you got some of the "winter mix" gas with higher ethonol" in your earlier post. Then the opposite statement above saying the ethanol content isn't changed.

 

[Gibby13]

We are averaging 13.6mpg with 4,100 miles so far with the 6.2 in our '21 Yukon XL Denali

 

[Thislife1977]

Hi guys,
I bought a 21 Tahoe RST back in February. Before that I had an '18 Suburban and before that a '15 Tahoe. My wife likes a new truck every few years and drives primarily in suburbia as a school bus for our kids. Our driving habits have not changed however on this new Tahoe, we have been averaging about 8 mpg. It's advertised as 14 mpg city but were getting barely 1/2 of that. Anyone else experiencing a similar issue? We are at the pump almost weekly. It's a complete disappointment. I've had it in for servicing once under warranty already for an SRS light but they didn't note anything unusual. Any suggestions? Thanks for the help!

I recently purchased an AT4 and was getting crap gas mileage 8/9 mpg. My dumbazz was running the vehicle in “auto” and not “2wd” smh. Not saying this is your issue but thought it was worth mentioning....just in case.

 

[Bagherra]

I recently purchased an AT4 and was getting crap gas mileage 8/9 mpg. My dumbazz was running the vehicle in “auto” and not “2wd” smh. Not saying this is your issue but thought it was worth mentioning....just in case.

Does make a significant difference?

 

[Stbentoak]

Auto means that the four-wheel-drive only engages when needed. It would make a slight difference possibly, but not a significant difference. Many people leave their vehicle in auto all the time. Not a factor overall....

 

[fasteddy]

I have a 6.2/10L90 and get what I consider magical mileage.
I get 25mpg on the hwy easy.....best is 32 over a 300 mile stretch.
But in the city its like 11 but I throttle it everywhere.....flooring this thing to 50mph is just fun

Its definitely your miles/hour ratio

The diesels are very cool.....
But so is the new F150 with a 300 mile range......and 750lbs of TQ!
Where's the affordable GM electric chassis? They are falling behind.

If you only average 10 miles per hour (of engine run time) electric would be a better option for you.