NV4500 Manual Trans for 1999-2002 GM Pickup, 6.5L 2WD

Description

Meet strict commercial flatbed fleet uptime standards with 190 lbs of cast iron drivetrain engineering that directs 440 lb-ft torque through 5 computer-matched forward gear steps in the GM Sierra 6.5L NV4500 Remanufactured Transmission built for 1999 to 2002 Chevrolet Silverado and GMC Sierra two-wheel drive commercial pickups powered by 6.5L turbodiesel engines.

The high-strength cast iron main housing supports deep-tooth helical gear sets, induction-hardened shift forks, and heavy tapered roller bearings. An engineered cast aluminum top cover houses internal shift rails with positive detent lock balls to prevent gear hop-out. The transmission weighs 190 lbs dry, holds 4.0 quarts of Syntorq manual gear lubricant, and incorporates a standard rear slip yoke extension housing.

Key Features of GM Sierra

Commercial transport fleets choose to buy GM Sierra manual transmission packages to eliminate chronic second gear synchronizer slip and restore dependable heavy cargo transit. Precision bearing shimming prevents countershaft end-play under high payload demands.

• 5-speed manual gear ratios feature an updated 5.61:1 low gear for dependable heavy breakaway pulling force.
• Heavy cast iron casing architecture resists structural deflection under full diesel engine torque output.
• Carbon-composite synchronizers prevent gear clash during rapid commercial driver upshifts.
• Tapered roller mainshaft bearings hold exact shaft end-play tolerances under maximum trailer towing.
• GM Sierra NV4500 units incorporate updated mainshaft locknuts to eliminate fifth gear slip.
• Viton input and output seals prevent gear fluid leakage under high continuous sump temperatures.
• Magnetic fluid drain plugs collect fine iron debris to protect internal needle and roller bearings.

Thermal Sump Limits Mechanical Step Data

Engineered to handle 440 lb-ft continuous input torque at 3,000 RPM, this manual gearbox handles heavy commercial hauling without gear face distress. Structural iron casing walls dissipate gear friction to maintain lubricant temperatures below 190°F. Forward gear steps provide 5.61:1 first gear, 3.04:1 second gear, 1.67:1 third gear, 1.00:1 fourth gear, and 0.73:1 fifth gear.

Axle Journal Runout Flange Dimensions

The transmission output shaft incorporates a 31-spline slip interface machined for exact driveshaft yoke engagement. Extension housing journal runout remains within 0.001-inch limits, preventing secondary harmonic vibration down the driveline. Bell housing bolt patterns mate flush with GM diesel bell housings using precision dowel guide pins.

Shift Calibration Protocol Service Limits

Bleed the external clutch hydraulic slave cylinder to establish crisp clutch disengagement before operational testing. This transmission is not engineered for truck pull competitions, engine builds exceeding 400 horsepower, or vehicles exceeding 18,000 lbs gross combined weight ratings.

• Inspect clutch hydraulic lines and slave cylinder fittings for fluid sweat every 15,000 miles.
• Drain and replenish gear oil with approved synthetic 75W-85 manual transmission fluid every 30,000 miles.
• Inspect transmission support crossmember bolts and rubber isolator bushings every 12 months.

Commercial Warranty Freight Shipping Manifest

Supplied with a 3-Year / 100,000-Mile commercial fleet warranty covering components and certified shop labor. The heavy shipping box holds the fully remanufactured five-speed manual gearbox, shifter tower gasket, clutch guide tool, installation guide sheet, and dynamometer verification documentation.