Unitrax Differential Services

UNITRAX DIFFERENTIAL SERVICES — A Division of JBM Offroad

Serving Southern California since 1986, Unitrax Differential Services specializes in professional differential repair, rebuilding, ring and pinion installation, re-gearing, and differential locker installation. Located in Corona, California, we provide drivetrain services for passenger cars, classic vehicles, Jeeps, trucks, SUVs, commercial vehicles, and off-road applications.

Whether your vehicle needs a complete differential rebuild, replacement bearings and seals, new ring and pinion gears, or improved traction through a locking differential, our experienced technicians provide precision drivetrain solutions designed for reliable performance.

In addition to servicing vehicles at our facility, Unitrax supports independent repair shops, automotive businesses, and fleet operators throughout Southern California. We rebuild complete differential assemblies, third members, and axle assemblies for customers who prefer to remove and deliver their components for professional rebuilding.

Call (951) 372-0200 to discuss your differential repair needs or request a quote.

Professional Differential Repair & Drivetrain Services

Unitrax provides specialized differential and drivetrain services for both everyday vehicles and demanding commercial or performance applications. Our services include:

• Differential Repair & Rebuilding: Diagnosis and repair of worn or damaged differentials, including replacement of bearings, seals, gears, and other internal components.
• Ring & Pinion Installation: Professional installation and precise adjustment of ring and pinion gear sets to achieve proper gear contact patterns, backlash, and reliable operation.
• Re-Gearing & Gear Ratio Changes: Changing differential gear ratios to accommodate larger tires, towing requirements, improved acceleration, or specialized vehicle applications.
• Differential Locker Installation: Installation of locking differential systems designed to improve traction for off-road vehicles, work trucks, and performance applications.
• Limited-Slip Differential Upgrades: Installation and servicing of limited-slip and positraction differential systems for improved traction and vehicle performance.
• Axle & Differential Assembly Service: Repair and rebuilding of axle assemblies, third members, and complete differential units for individual customers and professional repair shops.
• Commercial & Fleet Differential Service: Differential repairs and rebuilding for commercial trucks, delivery vehicles, work trucks, and fleet applications.
• Classic & Performance Vehicle Differentials: Differential rebuilding and gear ratio upgrades for classic cars, muscle cars, restoration projects, and performance vehicles.

Signs Your Differential May Need Repair

Differential problems often develop gradually. Recognizing the warning signs early can help prevent additional damage and expensive repairs.

• Whining or Howling Noises: Unusual noises that change with vehicle speed or acceleration may indicate worn bearings, improper gear contact, or damaged ring and pinion gears.
• Clunking or Banging: Excessive drivetrain noise during acceleration, deceleration, or shifting may indicate worn or damaged differential components.
• Vibration: Unusual drivetrain vibration may result from worn bearings or other drivetrain problems requiring inspection.
• Differential Fluid Leaks: Oil leaking around axle seals, pinion seals, or differential housings can lead to insufficient lubrication and internal damage.
• Excessive Play or Unusual Movement: Excessive drivetrain backlash or abnormal movement may indicate worn gears, bearings, or related components.

If your vehicle is experiencing these symptoms, contact Unitrax to discuss inspection and repair options.

The Unitrax Precision Differential Rebuilding Process

Proper differential rebuilding requires specialized knowledge, accurate measurements, and careful attention to gear alignment and bearing adjustment.

At Unitrax, differential repairs and rebuilds may include:

• Complete Component Inspection: Inspection of ring and pinion gears, bearings, seals, differential cases, and related internal components.
• Ring & Pinion Contact Pattern Verification: Checking gear tooth contact patterns to ensure proper alignment and operating characteristics.
• Backlash & Pinion Depth Adjustment: Precision measurement and adjustment according to applicable manufacturer specifications.
• Bearing Preload Adjustment: Proper bearing installation and adjustment to support reliable differential operation.
• Quality Replacement Components: Use of appropriate replacement bearings, seals, and gear components selected for each application.

Differential Re-Gearing for Larger Tires & Performance

Installing larger tires changes the effective final drive ratio of a vehicle. This can affect acceleration, towing performance, transmission behavior, and overall drivability.

Changing the differential gear ratio can help restore performance and improve the vehicle's suitability for its intended use.

For example, vehicles equipped with larger off-road tires may benefit from gear ratios such as:

• 35-inch Tires: Depending on the vehicle, engine, transmission, and intended use, ratios such as 4.56 or 4.88 may be considered.
• 37-inch Tires: Some applications may benefit from ratios such as 4.88 or 5.13, depending on vehicle specifications and driving requirements.

The correct gear ratio depends on several factors, including tire size, vehicle weight, engine characteristics, transmission ratios, axle type, and intended driving conditions.

Our team can help determine an appropriate gear ratio for your application.

Differential Gears, Lockers & Quality Components

Unitrax works with differential components and drivetrain products from established manufacturers, including:

Dana Spicer, AAM, Eaton, Yukon Gear & Axle, Richmond, US Gear, Motive Gear, and ARB.

Differential Rebuilding for Automotive Repair Shops

Unitrax provides differential rebuilding services for independent automotive repair shops, mechanics, and businesses that need specialized drivetrain work.

Repair shops can arrange to deliver differential assemblies or third members for inspection, repair, or rebuilding.

This allows automotive service businesses to offer professional differential repairs without maintaining specialized differential rebuilding equipment or performing the work in-house.

Contact Unitrax to discuss your assembly, application, and service requirements.

Examples of Differential Repair & Rebuilding Work

Differential Services for Cars, Trucks, SUVs & Commercial Vehicles

Unitrax provides differential repair and rebuilding services for a wide range of vehicle applications, including:

Precision Engineered. Field Proven. Since 1986.