I think the following the 2005 Xterra will be sharing the same engine with Frontier.

and the number is:

http://www.nissanhelp.com/News/Most%20Powerful%20V6%20Pickup.htm

"Nissan North America, Inc. today announced best-in-class horsepower and torque ratings for the all-new Nissan Frontier pickup, which goes on sale at Nissan dealerships nationwide in December 2004. The completely redesigned 2005 Frontier comes equipped with an available 4.0-liter DOHC, 24-valve V6 engine that is rated at 265 horsepower and 284 lb-ft of torque. Both figures are expected to be the highest ratings for any V6-equipped pickup – mid-size or full-size."