Gas Mileage for Trip

[Lynchr]

Members are always asking about gas mileage so thought I would post this:

Just returned from 1,200 mile trip in the 06 M35X. The vast majority of it was as 80 mph and I averaged 23.1 mpg as calculated by miles driven divided by gallons of gas used. At that speed in an X I am very satisfied. FYI - It has 62,000 miles on it now.

[wingFeather]

Thanks for the report! I have over 100,000 miles & get about the same. On flat land I'm able to get 25... but flat land is hard to find around here!

[GenericM35]

Out of curiosity, do you remember what the car's computer showed for that trip? In the last 800km (~500mi) trip I did, I got around 11l/100km (21.5mpg) mostly doing 120km/h (75mph), but this was what was displayed on the car's computer. Unfortunately, I didn't measure it myself. I was wondering if this is similar to what your computer showed.

[Lynchr]

Out of curiosity, do you remember what the car's computer showed for that trip? In the last 800km (~500mi) trip I did, I got around 11l/100km (21.5mpg) mostly doing 120km/h (75mph), but this was what was displayed on the car's computer. Unfortunately, I didn't measure it myself. I was wondering if this is similar to what your computer showed.

I just knew this question was coming. I didn't reset the computer before the trip so can't give you any definitive data. Historically the computer mileage has been very close (+/- 1.5 mpg) to actual.

My trip was a mix of flat, hills, and mountains. Most of it was hills.

I've driven my 430 hp Vette over the same route, at same speeds, many times and get between 27 and 29 mpg. The Vette is lighter (3,300 #) and has a six speed auto. At 80 mph the M is turning 3.300 rpm and the Vette is only turning 1,700 rpm.