Segment:
Mid-size utility ATV segment, offering a balance of power, agility, and features for recreational and light-duty work.
Key Competitors:
Honda FourTrax/Rancher, Yamaha Kodiak/Grizzly, Kawasaki Prairie/Brute Force, Suzuki King Quad.
Powertrain Options:
Available in 287cc and 375cc (HO - High Output) engine variants, both typically single-cylinder, liquid-cooled.
Drivetrain Type:
Selectable 2WD/4WD with Automatic PVT (Polaris Variable Transmission) and engine braking.
Suspension Type:
Independent Front Suspension (IFS) and MacPherson Strut Rear Suspension (on some models) or Dual A-Arm Rear Suspension, providing good ground clearance and ride comfort.
Utility Features:
Front and rear racks for cargo carrying, tow hitch capability (standard on many models), and typically a sealed storage compartment.
Benefit:
Empowers owners and technicians with the knowledge to maintain, diagnose, and repair their 2008 Polaris Sportsman effectively, reducing reliance on expensive dealership services.
Primary Coverage:
Complete service, repair, and maintenance for 2008 Polaris Sportsman 300 and Sportsman 400 HO ATVs.
Secondary Coverage:
Troubleshooting, diagnostics, specifications, wiring diagrams, and component identification.
Estimated Pages:
Extensive (typically 500+ pages for a complete workshop manual, though not explicitly stated).
Type:
Workshop Service Repair Manual
Engine:
Detailed procedures for engine disassembly, assembly, inspection, and repair of both 287cc (Sportsman 300) and 375cc (Sportsman 400 HO) engines. Includes cylinder head, piston, crankshaft, camshaft, valve train, cooling system, lubrication system.
Transmission:
Coverage for the automatic transmission (PVT - Polaris Variable Transmission), including belt inspection/replacement, clutch system, and gearbox service. Details on centrifugal clutch and drive/driven clutch maintenance.
Drivetrain:
Includes front and rear differential service, driveshafts, CV joints, and final drive units. Specific procedures for AWD engagement and maintenance.
Suspension:
Front and rear suspension component inspection, service, and replacement. Includes A-arms, shocks, bushings, and wheel bearings. Procedures for adjusting spring preload.
Brakes:
Hydraulic brake system service, including master cylinders, calipers, brake pads, brake lines, and bleeding procedures. Parking brake adjustment and service.
Electrical System:
Comprehensive coverage of the electrical system, including battery, charging system (stator, regulator/rectifier), starting system (starter motor, solenoid), ignition system (CDI, spark plugs), lighting, switches, and accessories. Includes detailed wiring diagrams.
Fuel System:
Carburetor (likely Mikuni BSR series) service, cleaning, and adjustment. Fuel pump, fuel lines, and fuel tank maintenance. Fuel filter replacement.
Cooling System:
Radiator service, fan operation, coolant replacement, thermostat testing, and water pump inspection.
Frame And Bodywork:
Procedures for body panel removal/installation, seat service, handlebar replacement, and frame inspection. Includes rack systems.
Maintenance:
Regular scheduled maintenance, including oil changes, filter replacements, air filter cleaning/replacement, spark plug service, chain/belt inspection, and lubrication points.
Troubleshooting:
Systematic diagnostic procedures for common and uncommon issues, including starting problems, engine performance issues, electrical faults, and braking system malfunctions.
Repair:
Step-by-step instructions for component disassembly, repair, reassembly, and adjustment across all major vehicle systems.
Diagnostics:
Includes diagnostic charts, voltage/resistance checks, and interpretation of symptoms to pinpoint problems.
Depth:
Comprehensive from basic owner maintenance to in-depth engine rebuilds, transmission overhauls, and electrical system diagnostics. Suitable for professional mechanics and experienced DIY enthusiasts.
Engine Type:
Liquid-cooled, 4-stroke, SOHC, 2-valve (Sportsman 300) / 4-valve (Sportsman 400 HO)
Displacement 400 Ho:
375cc
Horsepower Estimate:
Approx. 24-28 HP for Sportsman 300, Approx. 30-33 HP for Sportsman 400 HO (figures may vary by region/tuning).
Torque Estimate:
Specific torque figures are not readily available but designed for utility and trail performance.
Carburetor Model:
Likely Mikuni BSR series (e.g., BSR33/34).
Fuel Type:
Unleaded Gasoline (87 Octane minimum recommended).
Ignition Type:
CDI (Capacitor Discharge Ignition)
Cooling Method:
Liquid Cooling
Transmission Type:
Automatic PVT (Polaris Variable Transmission) with Engine Braking
Gear Selection:
High (H), Low (L), Neutral (N), Reverse (R), Park (P).
Optional Transmission:
N/A (All models featured the PVT automatic transmission).
Drive Engagement:
Centrifugal clutch automatically engages at higher RPMs.
Transmission Fluid Spec:
Polaris AGL Synthetic Gearcase Lubricant or equivalent SAE 75W-90 Synthetic Gear Oil. Refer to manual for exact specifications and capacities.
Atv Safety Standards:
Meets ANSI standards for recreational ATVs. All riders should wear appropriate protective gear (helmet, goggles, gloves, boots, long sleeves, long pants).
Braking System:
Hydraulic disc brakes front and rear, with a sealed hydraulic rear braking system. Engine braking integrated into the PVT.
All Wheel Drive:
On-demand AWD system that engages the front wheels when rear wheel slippage is detected.
Lighting:
Dual headlights and a rear brake light/taillight.
Operator Presence:
Thumb throttle with safety interlock, handlebar brake levers with integrated parking brake function.
Engine Oil Change:
Every 100 hours or annually, whichever comes first. Check manual for specific operating conditions.
Air Filter Inspection:
Every 20 hours or every 3 months. Clean/replace as needed based on operating conditions (dusty environments require more frequent checks).
Spark Plug Service:
Inspect every 100 hours or annually. Replace as needed.
Transmission Fluid Check:
Inspect every 100 hours or annually. Change as per manual recommendation.
Drive Belt Inspection:
Inspect every 50 hours or annually. Replace if wear or damage is evident.
Engine Oil Type:
Polaris PS-4 5W-50 Full Synthetic 4-Stroke Engine Oil or equivalent API SG/SH/SJ rated oil.
Engine Oil Capacity:
Approx. 2.1 US quarts (2.0 Liters) with filter change. Refer to manual for exact capacity.
Coolant Type:
Ethylene Glycol based antifreeze (e.g., Polaris Premium Antifreeze) mixed 50/50 with distilled water.
Brake Fluid Type:
DOT 3 or DOT 4 Hydraulic Brake Fluid.
Common Wear Items:
Drive belts (especially under heavy use), ball joints, tie rod ends, wheel bearings, suspension bushings, and brake pads are common wear items on ATVs of this era.
Potential Issues:
Carburetor tuning can be sensitive to altitude and temperature changes. Water intrusion into CV boots or differentials can occur if seals are compromised. Some earlier models experienced stator issues, though less common by 2008.
Oil Filter Part Number:
Polaris 3070005 (check for superseded part numbers).
Air Filter Part Number:
Polaris 7074079 (check for superseded part numbers).
Manufacturer:
Polaris Industries is a long-standing American manufacturer of powersports vehicles, known for its innovation in ATVs, snowmobiles, and motorcycles.
Sportsman Lineage:
The Sportsman line has been a cornerstone of Polaris's ATV offerings since the early 1990s, evolving through various displacements and feature sets, emphasizing comfort, utility, and capability.
2008 Updates:
The 2008 models represented refinements within the Sportsman platform, offering a 287cc option for entry-level riders and the popular 400 HO for more performance-oriented use, both featuring the established chassis and suspension.
Manufacturing Location:
Polaris ATVs are primarily manufactured in Roseau, Minnesota, USA.
