Not sure why you are thinking of buying a second car? I'm assuming that means you'd then have 3 vehicles?
I think it's safe to say that you like your Ranger and would rather not give it up. So,, how much is it worth to you to keep it and do the new commute? I figure it would be about $190/ month (this is just for added fuel expense per month).
The math:
Your new commute would be about 2,400 km / month (120 per day x 5 days x 4).
I'm gonna be generous and say the Ranger will return 14L/100 on that commute. So, 336L per month x $1.30 per = ~ $440 per month
Your current commute is about half that, so added expense is about $220 / mo
Lets say you trade the Ranger and buy a nice boring appliance like a Corolla/Civic/ whatever.
That should pretty easily get you 8L/100, so 192L per month x $1.30 per = ~ $250 per month
So with a boring (but cheap & reliable!) appliance, your added exp is roughly $30 per month.
Is it worth the extra $190/ mo to keep the Ranger?
I wouldn't be worried about the mileage itself & maintenance costs, etc.. you'd be putting on the vehicle - you'd have to deal with that no matter what you drive.
OR..... you take the G5 and your GF takes the stRanger.
