Grand Highlander Platinum Max gas mileage and range

One of the big reasons I went with the Grand Highlander over my ICE Tacoma (manual) was better gas mileage. I regularly got 22+ mpg out of the Taco, but after several 500+ mile road trips I'm lucky to break 20 mpg in the GH - no towing, no heavy loads, and I'm not exactly lead-footing it.

I also feel like I'm constantly at the pump compared to the Tacoma, which is frustrating. The dealer's response? "Oh, that's normal for our altitude and winter." But this winter has been pretty mild, so I'm not buying it.

At this point, I'm seriously considering trading it in for a Tundra. If I'm stuck at 20 mpg anyway, I'd rather have double the towing capacity, room to throw some drywall in the bed, and 350+ miles per tank.

Anyone else feeling the pump-chump pain, or is it just me?