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2018 Terrain Denali Terrible MPG

4K views 15 replies 8 participants last post by  c&wsinbad 
#1 ·
Hello,

I have had a Terrain Denali for 1.5 years in a cold weather climate. I drive a combination of city and highway miles everyday, about 50/50. I use auto start during the winter and currently average 15.4 MPG. My fuel gauge seems to move lower during every drive. I fill up at least once a week.

I know it’s a turbo, it’s cold out etc... but is sub-16 MPG really correct? Anyone else having low gas mileage like this?

Thanks,
Grasher
 
#2 ·
How long to you remote start the car compared to your drives ? With the same engine, I don't think I have ever gotten below ,27, but my trips are 80+90% highway, and I don't use the remote start.
 
#4 ·
Mine is a 2018 SLE 1.5L FWD model that is always remote started before leaving home, and all of my driving has been of the short trip variety with just a little spirited driving now and then but not pushing it. I also make sure the engine gets a full warm-up with each drive cycle.

I calculate each fill-up by hand, and I'm averaging 18.34 mpg. Weather has been mild this season, but it has gone down to the low 20's on occasion.

The Eco page indicates an average fuel economy of 20.6 mpg with a best average economy of 20.8 mpg for the last 450 mi.
 
#7 ·
How cold of a climate do you drive in ? Are there hills/mountains ? Do you use snow tires ? Do you use AWD or just FWD ? Does your State use a Winter Blend gasoline ? How much above 70 do you drive ? How many passengers in you car ? What is you tire pressure ?



All of the above will cause a hit in MPG, plus, as you mentioned, not getting into 9th gear.


I am not sure how much of an overdrive 9th gear is compared to 6th gear in my 6-speed automatic, but certainly, all of my highway driving is in 6th gear.
 
#9 ·
I am not 100% sure, but as I recall, the 6-speed Equinox had a higher Highway EPA rating than the 9-speed Terrain. This was discussed on the forum, but I don't recall what the explanation was, but someone was able to rationalize it. I couldn't !
 
#13 ·
The 2.0L in the Denali gets worse mileage then the 1.5L. My Denali I'm averaging about 20.1 mpg on shorter highway trips averaging around 15 minute drive doing 75-77mph and using the AWD. I usually use the remote start when leaving work and it runs about 5 minutes before I get in and go. 16mpg seems a bit low IMO.
 
#14 ·
I don't have the heart to drive our new denali in winter yet.. I've had it out a few times but it pains me to see it with salt on it so I've been taking the beater car whenever possible.. We've had the terrain out a few times with the blizzak snow tires and MPG definetely takes a hit but still above 20mpg... It was 23.5 mpg on the last winter drive of about 75mi. at approx 55mph. I can coax 30mpg out of it in summer but have to stay out of the turbo and accelerate slowly
 
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