3.5L

Just returned home today from a 4325 mile trip through the northwestern states. Trip computer indicated exactly 25.0 for the entire trip. For the past few days it had been hovering at 24.9, but it bumped to 25.0 today when we averaged 25.7 on our last leg home.

Yesterday, we logged 27.9 on the leg from Boise, ID to Winnemucca, NV.

Now I'm left wondering why the EPA highway rating is only 21. 4325 miles isn't exactly a short trip, so I think our 25.0 MPG is very realistic.

3.5L

Oldengineer

Wife and I have made trips from WV to MO in both of our little SUVs. We discovered that our Mercedes gets better average mpg on these trips than our Honda CRV does. Apparently running 70 - 75 MPH on the interstate isn't the Honda's forte.

Regards:
Oldengineer
2011 GLK 4Matic
2010 Honda CRV LX 2WD
1948 Chevrolet Fleetmaster Town Sedan

MBNA109

3.5L - what speeds are you operating at?

We notice that 70-75 like Oldengineer is referencing allows optimal MPG (25 mig-ish).
However, as you bump it towards 80 & above it incrementally gets less obviously but we still get in the 23's.

venchka

A hunch, based on doing the arithmetic for some long highway jaunts, is that the trip display is a couple MPGs optimistic. Still, 23mpg isn't too shabby.

Wayne

rmfnla

Hwy speeds stress a 4 cylinder more than a 6...

MBNA109

Ha - I haven't done the odometer mileage divided by printed gallons on the receipt math in awhile.
Thanks for reminding me to go back to the basics!

Oldengineer

The problem with the Honda is its torque curve - its very peaky and doesn't make any suds until very high RPM. Consequently, at every little rise in the road, it has to downshift and scream its guts out to maintain speed. Honda needes to redesign the engine to make its torque curve mesa shaped.



Regards:
Oldengineer

3.5L

Speeds were all over the map. We cruised for hours at 75 out in the boonies, yet found ourselves at 55 for hours in constructions zones. Some parts of highway 101 in Oregon and Washington got down to 35 MPH stretches. Still, I didn't hesitate much to hit 90 MPH passing a line of trucks on two-lane highways. Also did a fair amount of city driving.

Summary is that I don't flog my GLK much. When I need to, I'll punch it to get by traffic, but most of the time I accelerate with traffic and enjoy the smooth, quiet ride.

3.5L

3.5L

Don't consider this absolute, but when I made a 1400 mile round trip to Tucson last April, I used our gasoline receipts and Rand-McNally road distance calculators to check the computer MPG calculations and they were within .1 MPG of each other. On that trip, we cruised at 70 to 80 quite a bit, with the AC on.

3.5L

iewoals

I find my trip computer to be fairly accurate as well. I run the numbers in my head at each fill up. I think for the most part the computer is within 0.5 to 1 mpg.

NCBob

400 mile trip last week. Combo of interstate and 2-lane.
Averaged 23MPG. A/C on full time. I'm OK with that.
Got 30MPG on my C-300 earlier this year w/o A/C on