Zumbrota Drivetrain RAA435-1837A Remanufactured Rear Axle Assembly GM 8.5" 3.42 Ratio 5-Lug

The Zumbrota Drivetrain RAA435-1837A is a remanufactured complete rear axle assembly built around the GM 8.5" 10-bolt platform. Featuring a 3.42 gear ratio (RPO GU6) and 5-lug semi-float axle configuration, this drop-in replacement is engineered to restore OEM drivetrain performance without the cost of a new unit.

Remanufacturing Process:

• Each axle assembly is thoroughly inspected for straightness, cracks, and surface wear
• All internal components are fully inspected and tested, including ring & pinions, internal gears, clutches, and carriers
• All bearings and seals are replaced during every rebuild
• Gears are verified for optimal tooth contact patterns and correct rolling torque using inch-pound measurements for precise setup and long-term reliability
• Correct gear backlash is set to ensure proper lubrication and quiet operation
• Axle tubes are inspected and confirmed to OEM standards of straightness
• Exclusive hydro-blast rinse and sandblasting procedure applied to all internal and external parts, followed by a proprietary deep-cleaning process

Key Specifications:

• Axle Type: GM 8.5" 10-Bolt Ring Gear
• Gear Ratio: 3.42 (RPO Code GU6)
• Lug Configuration: 5-Lug
• Differential Type: Open (without Posi-Traction)
• Note: Does not include hubs, brakes, backing plates, or axle shafts

Warranty: Backed by Zumbrota's standard 2-year/unlimited mileage warranty for 3/4-ton and lighter applications. An optional no-fault 3-year warranty upgrade is also available, covering labor, towing, rental car, and freight charges.

Zumbrota Drivetrain has served a nationwide customer base for over 30 years, offering remanufactured drivetrain components from their 60,000 sq. ft. facility in Zumbrota, Minnesota. The RAA435-1837A is a core-required unit — a refundable core charge applies at the time of purchase.