The 2008 Itasca Horizon 40TD is a highly regarded Class A diesel pusher motorhome, produced by Winnebago Industries (Itasca being a Winnebago brand). It's built on the advanced Maxum Chassis, offering a powerful ride and extensive features.

Here's a comprehensive overview of its specifications:

Key Features & Layout:

• Floor Plan: The 40TD features a layout designed for spacious living. It typically includes a front kitchen, a central living area with a sofa and dinette/chairs, a split bath (or a private central bath) with double entry, and a rear master bedroom with a queen bed and a slide-out for wardrobes/dressers.
• Sleeping Capacity: Typically sleeps 4 people.
• Slides: Features 2 large slide-outs (one encompassing the bedroom and often a bench seat/wardrobe, and another for the dinette/sofa and kitchen elements).
• Unique Features: Known for its large cross-coach storage in the basement due to the Maxum Chassis's lowered-rail design.

Chassis & Engine:

• Chassis: Maxum Freightliner Chassis (Winnebago's proprietary Freightliner chassis with a lowered-rail design).
• Engine: Cummins® ISL 8.9L turbo-charged diesel engine.
• Horsepower: 425 hp @ 2,200 RPM 
• Torque: 1,200 ft-lbs. @ 1,300 RPM.
• Transmission: Allison® 6-speed 3000 MH transmission with Overdrive.
• Fuel Capacity: 100 gallons.
• Alternator: 170 amp.
• Brakes: 4-wheel ABS.
• Hitch: 10,000 lb. trailer hitch with 7-pin connector.
• Stylized Aluminum Wheels.

Dimensions & Weights:

• Length (Exterior): 39 ft 10 inches 
• Exterior Width: 8 ft 6 inches (101.5 inches).
• Exterior Height (with AC): 12 ft 4 inches.
• Interior Height: 7 ft 2 inches (86.5 inches).
• Hitch Weight/Towing Capacity: 10,000 lbs.
• GVWR (Gross Vehicle Weight Rating): 34,320 lbs.
• GCWR (Gross Combined Weight Rating): 44,320 lbs.
• UVW (Unloaded Vehicle Weight): Approximately 29,143 lbs (varies by options).
• GAWR Front (Gross Axle Weight Rating Front): 14,320 lbs.
• GAWR Rear (Gross Axle Weight Rating Rear): 20,000 lbs.

Tank Capacities:

• Fresh Water Capacity: 103 gallons.
• Grey Water Capacity: 117 gallons.
• Black Water Capacity: 51 gallons.
• Propane Capacity: 31 gallons (approximately 131 lbs).
• Water Heater Tank: 10 gallon (Gas/Electric with Electronic Ignition DSI).

Appliances & Utilities:

• Refrigerator: 4-Door Refrigerator/Freezer (Residential French-door refrigerator optional).
• Cooktop/Oven: 3-burner Range with Oven.
• Microwave Oven: Convection Microwave Oven.
• Furnace BTU: Dual Zone Electronic Ignition Furnaces: 40,000 BTU (for 40TD). Some sources mention 65,000 BTU total.
• AC BTU: TrueAir® Residential Central Air with heat pump (ducted, with heat pumps). Dual 13,500 BTU roof A/C units.
• Electrical Service: 50 amp power cord.
• Generator: 8,000 watt Cummins Onan Quiet Diesel Generator on manual slide-out.
• Batteries: 3 deep cycle coach batteries. Battery disconnect system. Auxiliary start circuit.
• Inverter: 2,000-watt inverter (often standard with residential fridge option).
• Awning: Automatic Patio Awning (often 20 ft). Automatic Front Door Awning. Topper slide-out awnings (living area and bedroom). Window awnings on all slide-out house windows (except under patio awning).
• Entertainment: 37" LCD high-definition TV in the living area. 20" LCD color TV in the bedroom. Home Theater Sound System (CD/DVD player, receiver, amplifier, 5 speakers, subwoofer, Sony). Stereo System in Bedroom (AM/FM stereo, CD/DVD player, headphone jack). RV Radio® (Cab) AM/FM stereo/CD player, iPod/MP3-ready. Optional exterior entertainment center. Optional satellite dish antenna (digital, automatic King-Dome or in-motion dual LNB King-Dome).
• Leveling Jacks: HWH® hydraulic leveling jacks with 3-position controls.

Construction & Exterior:

• Body Material: Aluminum body construction.
• Sidewall Construction: Fiberglass sidewalls.
• Roof: Fiberglass Roof.
• Windows: Dual-glazed thermo-insulated windows (frameless on some models).
• Storage: Large cross-coach storage due to Maxum Chassis design. One-piece polyethylene pass-through storage compartment. Side-hinged baggage doors. Pullout generator tray with one-piece door.
• Entry: Electric Flush-Floor Stepwell Cover. Automatic electric entry step. Keyless entry with remote.
• Mirrors: Chrome Dual Head Power Controlled Heated Exterior Mirrors with Turn Indicator Lights.
• Full-Length Mud Flap.
• 3M Film Front Mask.
• Rear Ladder.
• One-Piece Windshield.

Interior Features:

• Decor: Various interior color schemes (e.g., Garden View with Honey Cherry). Ceiling vinyl.
• Cabinetry: Raised panel hardwood cabinet doors. Hardwood cabinet end panels. Heavy-duty ball bearing drawer guides. Oil Rubbed Bronze Cabinetry Hardware and Bath Accessories.
• Flooring: Ceramic tile in kitchen and bath. Carpet in living area and bedroom.
• Kitchen: Solid Corian® countertops with polished radius edge. Stainless steel sink with two sink covers. Pullout countertop extension with drawer and Corian® top. Pull-out pantry.
• Living Area: UltraLeather™ Rest Easy sofa with dual controls (converts to a bed). Dining table and chairs. Pleated day/night shades. Hardwood entertainment center. Monitor system. Powered sunvisors.
• Bedroom: Queen or king Serta® innerspring mattress with pillows, bedspread & throw pillows. Padded bench with storage below. Reading lights. Wardrobe with storage cabinet or optional washer/dryer prep. Ceiling fan. Headboard. Full sliding privacy door.
• Bathroom: Angle shower with textured glass shower door and shower seat. Lavatory with linen cabinet and medicine cabinet. Shower light. Roof vent with rain sensor. Porcelain toilet.
• Cab Area: UltraLeather™ 6-way power-assist cab seats with armrests, manual footrest (passenger), adjustable lumbar support. SmartWheel™ steering wheel with controls. Color rearview camera system with audio. Power door locks with keyless entry.

Optional Features (Common):

• Residential Refrigerator.
• Washer/Dryer combination unit.
• Home Theater Lounge by Villa (recliners, UltraLeather).
• Sleep Number® bed.
• Exterior Entertainment Center.
• Exterior refrigerator/freezer on slide-out tray.
• Full-Body Paint.
• Solar Panel with 10-watt battery charger.

Important Note: As this is a 2008 model, it is a used vehicle. Specifications and the condition of components can vary significantly due to age, previous ownership, maintenance history, and any modifications.