Yep.

This is from the 2010 SD order guide:

FX4 OFF ROAD PACKAGE (17X)
Availability:
• Optional on XL, XLT and Lariat
Not available with:
• Pickup box delete (66D)
• Cabela's (17L) or Cabela's Luxury (17M)
Requires:
• 4x4, limited slip rear axle and All Terrain Tires
Includes:
• Transfer case and fuel tank skid plates
• Rancho branded shocks – colored front and rear shocks
• Unique "4x4 Off Road" box decal