Powertrains and Performance Three engines are available on the 2007 Toyota Tundra half-ton truck. Standard on the Tundra Regular Cab and standard-bed Double Cab is a 4.0-liter V6 rated for 236 hp and 266 pound-feet of torque. Optional on these models and standard on all other Tundras is a 4.7-liter V8 capable of 271 hp and 313 lb-ft of torque. Optional across the line is a much stronger 5.7-liter V8 good for 381 hp and 401 lb-ft of torque. The base V6 and 4.7-liter V8 use a five-speed automatic transmission. With either of these engines, your Tundra will have a 3.91 rear axle ratio unless you get the towing package, which provides a 4.10 ratio. The big V8 is paired with a six-speed automatic; 4.10 rear gears are standard and the tow package comes with a 4.30 ratio. All versions of the Tundra can be equipped with two-wheel drive or four-wheel drive, and all trucks come with a limited-slip rear differential. A properly equipped 4x2 Tundra Regular Cab can tow up to 10,800 pounds. The Tundra's maximum Gross Combined Weight Rating or GCWR (the total weight of the vehicle, including trailer, cargo, passengers and fuel load) is 16,000 pounds
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