The Lincoln Navigator L, the extended-length version of Lincoln’s large luxury SUV, returns for 2010 with no changes to its standard V8 engine.
The Navigator’s only engine is Ford’s 5.4-liter Triton V8. Also used by the Ford Expedition and F-Series trucks, this iron-block, aluminum-head SOHC engine is related to Ford’s 4.6-liter V8, but has a longer stroke and a forged-steel crankshaft. The 5.4 liter engine was introduced in 1997; it was extensively revised for 2004, getting a lightweight plastic intake manifold, freer-breathing cylinder heads with three valves per cylinder, and roller-type cam followers to reduce friction. It has a compression ratio of 9.8:1, which produces 310 horsepower and 365 pound-feet of torque.
In the Navigator, this engine has flex-fuel capability, allowing it to burn regular gasoline or blends up to 85% ethanol. Even on regular gas, the 5.4-liter V8 is very thirsty. The Navigator’s weight and class exempt it from EPA fuel economy tests, but reviewers say 12-13 mpg is typical, and hard driving can push mileage into the single-digit range. Running on E85 (an 85/15 blend of ethanol and gasoline) increases the already prodigious 5.4-liter fuel economy by more than 30%, but the EPA says it reduces greenhouse gas emissions by 10-11%.
The 5.4-liter engine feels a bit underpowered in the regular-length Navigator, and the L’s added weight further reduces its punch. The standard six-speed automatic makes the most of the available power, but the V8 doesn’t have enough power to let you forget about the Navigator’s three-ton mass. The Cadillac Escalade ESV, the Navigator L’s most direct rival, has a 403-horsepower 6.2-liter V8 that provides much more assertive performance. The Escalade also shares the Navigator’s flex-fuel capability. The Navigator L has a slight advantage in towing capacity, up to 8,700 pounds.