The Highlander is based on the Toyota Camry sedan and shares many attributes of the upscale Lexus RX350 and 400h SUVs. Due to its automobile platform, the Highlander looks like a genuine SUV, but drives like a car. Available in two- and four-wheel-drive configurations, although not built for dedicated off-roading, the 4-wheel drive version can hold its own.

The purpose of this trip was to see just how well Toyota’s patented hybrid gasoline-electric powertrain — called Hybrid Synergy Drive — performed on the open road. Hybrid Synergy Drive marries a 3.3-liter V6 engine with a high-torque electric motor-generator and electronically controlled continuously variable transmission, specifically developed to meet mid-size SUV load and performance needs. The combination produces 268 peak-combined horsepower, delivers 7.3 second 0-60 performance, with a 3,500-pound towing capacity. Touted as offering fuel economy akin to a four-cylinder compact car, it’s also rated as a Super Ultra Low Emissions Vehicle (SULEV).

With my 10-speed bike laying down across both rows of stowed rear seats, along with a suitcase, computer bag, hanging bag, and some munchies, I hooked up my XM Roady (no satellite radio installed in this Highlander) to play back through the sound system, plugged in my cell phone, and hit the road much later than I originally intended. I scooted down I-5, traveling opposite Portland’s 5 p.m. rush hour traffic, and made it to Roseburg, Oregon by 8 p.m.

I had done several errands after fueling up before leaving, and the first tank was refilled at 163.3 miles. It took 5.8 gallons of gas for 28.1 mpg. Not bad, considering much — but not all of that mileage was at 75+ mph. The next fill-up was 9.5 gallons just above Roseburg, after an additional 235.6 miles, registering 24.54 mpg. Just about all of that was at 75 mph or more.

The Highlander Hybrid 4x2 is EPA rated at 33/city and 28/highway, with a combined rating of 30. The 4WD-i (my test vehicle) is rated at 31/27 with a combined rating of 29. As I found out, actual mileage — at least on the open road — may vary. That first 28.1 was the best of the trip.

A little about the Highlander… Standard equipment includes three rows of seats, defroster-linked air conditioning with a cabin filter, power windows, mirrors and door locks, deluxe 3-in-1 AM/FM/ETR cassette/CD sound system with six speakers, remote keyless entry, tonneau cover, UV-reduction glass, cruise control, roof rack, rear privacy glass, power steering, and electronically controlled brakes.

Additional standard equipment either optional or not available on the conventional Highlander includes an eight-way power driver seat with power lumbar support, front-seat mounted side airbags with second row roll-sensing side curtain airbags, 17-inch five-spoke aluminum alloy wheels, in-glass antenna, daytime running lights, tow-prep package, HomeLink&Mac226; universal remote control system, engine immobilizer, mudguards, and a cold weather package featuring heated outside mirrors and a windshield de-icer grid.

The base Highlander Hybrid offers one option package which includes a JBL 3-in-1 AM/FM cassette with a six-disc in-dash CD changer and eight speakers in six locations and FM diversity reception, steering wheel audio controls, power tilt/slide moonroof with sunshade, integrated fog lamps, and a color-keyed rear spoiler.

The Highlander Hybrid also boasts Toyota’s Star Safety System — which includes Vehicle Stability Control (VSC), Traction Control (TRAC), Anti-Lock Brakes (ABS) with Electronic Brake-force Distribution (EBD) and Brake Assist (BA), all as standard equipment. Additionally, it offers Toyota’s Vehicle Dynamics Integrated Management (VDIM) system, which anticipates loss of vehicle control and makes automatic computerized corrections.

Other safety features include driver and front passenger advanced front airbags, plus front-seat mounted side airbags that include first and second row roll-sensing side curtain airbags.

Occupants sit high in the Highlander with a commanding view in big, supportive, comfortable seats. The low floor makes it easy to get in and out. The next morning I was on the road by 6 a.m. with a Starbucks in the cupholder.

The next gas stop was just south of Redding at 202.6 miles. It took 8.5 gallons for 23.84 mpg. The next one came 161.1 miles later, taking on 6.2 gallons for 25.98 mpg and another at 245.8, just north of Bakersfield where I turned off on Hwy 58, using 10.4 gallons for 23.63 mpg. I filled up at Barstow, Calif., with 10.3 gallons after 224.1 miles for 21.76 mpg, before hitting a local hotel for the night.

The next morning, fortified with an Egg McMuffin and a Starbucks to go, I headed out on I-40 around 6. By the time I hit Needles, usually the hottest spot in the country, a little after 8 a.m., it was already 99 degrees. Heading south on Hwy 95, I endured a half hour construction delay, hit I-10 at Blythe, crossed into Arizona and filled up in Quartzite 261.2 miles later. Taking on 13.3 gallons, averaging 19.64 mpg, I cruised into Scottsdale where the temperature was 102.

I spent four days in Scottsdale, parking the Highlander, while test-driving another vehicle. I headed out around 11 a.m., filling up near the 7th Ave entrance to I-10, with 7.8 gallons, which had taken me 150.6 miles, at 19.31 mpg.

The next stop was Needles, 261.8 miles away, where it was 106; gas was $3.99.9 for regular and $4.19.9 for premium. Luckily, the Highlander takes regular. It took 13.37 gallons averaging 19.58 mpg. From there, it was 270.2 miles through Barstow and Mojave and back over the pass to Bakersfield for the night. After putting in 13.41 gallons the next morning at 20.15 mpg, it was back across Hwy 58 to I-5. This became an 18-hour drive, getting me home at 1 a.m. after a brief nap in a rest area. Fill-ups were at 253.6 miles, 13.32 gallons, 19.04 mpg; 187.9 miles, 8.6 gallons and 21.85 mpg; 275 miles taking on 12.4 gallons for 22.19 mpg. The last one just south of Centralia at 226.7 miles, took 10.1 gallons averaging 22.46 miles.

Trip Notes: The Hybrid Synergy Drive is an extremely capable powertrain and at no time did I ever want for passing power on the freeway or the myriad of mountains and hills. Initially, I expected better overall average mileage than the 21.86 I got. But frankly, that’s still better than most mid-size SUVs at their best. Temperature and speed also have an obvious direct impact on fuel economy, and it bears noting that most highway speeds were in excess of 80 mph, with temperatures hovering around the 100-degree mark,. The trip also included twice crossing the pass between Bakersfield and Tehachapi and Siskiyou Pass at the Oregon-California border. As the sun went down, so did temperatures and speed — while mileage increased.

Bottom Line: The 4x2 base Highlander Hybrid carries an MSRP of $33,030, while the 4WD-i stickers at $34,430. The roomy Highlander was reasonably quiet and very comfortable during the long stretches. Driving 12+ hours at a crack, fatigue was minimal. Obviously, Toyota’s Hybrid Synergy Drive is most efficient in stop-and-go driving and at speeds under 70 mph — but this trip proved it can handle the highway at 100 mph in 100-degree heat, all day long. If you’ve had any reservations about buying a Toyota hybrid, forget them. This one’s a winner.