Motive Gear F9-350A Ring & Pinion Set Instruction Manual

1. Introduction

This manual provides comprehensive instructions for the installation, operation, and maintenance of your Motive Gear F9-350A Ring & Pinion Set. This high-performance gear set is designed to upgrade Ford 9" differentials, ensuring durability and efficient power transfer. Adherence to these guidelines will help ensure optimal performance and longevity of your differential components.

2. Product Overview and Components

The Motive Gear F9-350A is a 3.50 ratio ring and pinion set specifically engineered for Ford 9" differentials. It is manufactured from premium 8620 steel for superior strength and reliability.

Key Features:

• Premium 8620 Steel Construction
• Optimized 3.50 Gear Ratio
• 35-tooth ring gear, 10-tooth pinion gear
• 28-spline pinion shaft
• Standard rotation design
• Designed for Ford 9" axles with 10-bolt dropout carrier

What's Included:

• Ring Gear
• Pinion Gear

Image showing the Motive Gear F9-350A ring gear and pinion gear, highlighting their helical tooth design.

The Motive Gear F9-350A Ring & Pinion Set is packaged in a sturdy box, ensuring components are protected during transit.

3. Compatibility

This Motive Gear F9-350A Ring & Pinion Set is compatible with various Ford, Lincoln, and Mercury models equipped with a Ford 9" differential (1955-1986).

Compatible Ford Models:

• Bronco (1966-1986)
• E-100 Econoline (1969-1983)
• E-100 Econoline Club Wagon (1975-1983)
• E-150 Econoline (1975-1986)
• E-150 Econoline Club Wagon (1975-1986)
• E-200 Econoline (1969-1974)
• F-100 (1975-1983)
• F-150 (1975-1986)
• Fairlane (1957-1970)
• Galaxie (1959-1967)
• Galaxie 500 (1962-1974)
• Gran Torino (1972-1976)
• Granada (1975-1980)
• LTD (1965-1979)
• LTD II (1977-1979)
• Maverick (1970-1977)
• Mustang (1965-1973)
• Ranchero (1957-1979)
• Thunderbird (1955-1979)
• Torino (1968-1976)

Compatible Lincoln Models:

• Continental (1958-1979)
• Mark III (1968-1971)
• Versailles (1977-1980)

Compatible Mercury Models:

• Comet (1964-1969, 1971-1977)
• Cougar (1967-1979)
• Grand Marquis (1975-1978)
• Marauder (1963-1970)
• Marquis (1967-1978)
• Montego (1968-1976)

4. Setup and Installation Guidelines

Proper installation of a ring and pinion set is crucial for optimal performance and longevity. It is highly recommended that installation be performed by a qualified professional. Incorrect installation can lead to premature wear, noise, and differential failure.

Pre-Installation Checks:

• Inspect Components: Carefully unbox and inspect both the ring gear and pinion gear for any signs of damage during shipping. Ensure all teeth are intact and surfaces are smooth.
• Verify Ratio: Count the teeth on both the ring gear and the pinion gear to confirm the correct 3.50 ratio. Divide the number of teeth on the ring gear by the number of teeth on the pinion gear (e.g., 35 teeth / 10 teeth = 3.50).
• Cleanliness: Ensure all differential housing components are thoroughly cleaned and free of old lubricant, metal shavings, or debris.

Installation Steps (Summary):

The following is a summary of the general steps involved. Detailed instructions require specialized tools and knowledge, and professional installation is strongly advised.

1. Remove Old Components: Safely remove the existing differential components, including the old ring and pinion, bearings, and seals.
2. Install New Pinion Bearings and Seal: Install the new pinion bearings and seal onto the pinion shaft.
3. Set Pinion Depth: This is a critical step. Use specialized tools to set the correct pinion depth, which determines the contact pattern between the ring and pinion gears.
4. Install Ring Gear: Mount the new ring gear onto the differential carrier. Ensure all bolts are torqued to manufacturer specifications.
5. Install Carrier: Install the differential carrier assembly into the housing.
6. Set Backlash: Adjust the carrier shims to achieve the correct backlash between the ring and pinion gears. This is essential for quiet operation and proper gear mesh.
7. Verify Contact Pattern: Apply gear marking compound to the ring gear teeth and rotate the assembly to check the contact pattern. Adjust pinion depth and backlash as needed until an optimal pattern is achieved.
8. Final Assembly: Install new axle seals (if applicable), cover gasket/sealant, and fill with the recommended differential fluid.

5. Operating and Break-In Procedures

After installing new ring and pinion gears, a proper break-in procedure is essential to ensure long-term durability and quiet operation. This allows the gear sets to properly seat and harden.

Break-In Procedure:

1. Initial Drive: Drive the vehicle for 15-20 minutes under light load conditions (avoid heavy acceleration, towing, or aggressive driving).
2. Cool Down: Allow the differential to cool completely for at least 30 minutes. This prevents excessive heat buildup which can damage the gears.
3. Repeat Cycles: Repeat the 15-20 minute drive and cool-down cycle approximately 2-3 more times.
4. First 500 Miles: For the first 500 miles, avoid continuous highway driving at high speeds, heavy towing, or any activity that puts extreme stress on the differential. Vary your speed and load conditions.
5. Fluid Change: After the initial 500 miles, it is highly recommended to change the differential fluid. This removes any metal particles that may have worn off during the break-in process. Use a high-quality gear oil as specified by your vehicle manufacturer or a differential specialist.

Important Considerations:

• Avoid Overheating: Excessive heat is the primary enemy of new gears. If you notice the differential getting unusually hot, stop driving and allow it to cool.
• Listen for Noise: Pay attention to any unusual noises (whining, howling) coming from the differential. These could indicate improper installation or an issue with the gears.

6. Maintenance

Regular maintenance is crucial for extending the life of your differential and ring and pinion set.

Routine Checks:

• Fluid Level and Condition: Periodically check the differential fluid level and inspect its condition. Look for signs of contamination, excessive metal particles, or a burnt smell.
• Fluid Changes: Follow your vehicle manufacturer's recommendations for differential fluid change intervals. For vehicles used in demanding conditions (towing, off-roading), more frequent changes may be necessary.
• Leak Inspection: Regularly inspect the differential housing, pinion seal, and axle seals for any signs of fluid leaks.
• Noise Monitoring: Be attentive to any changes in differential noise during operation.

7. Troubleshooting Common Issues

This section addresses common issues that may arise with differential gears.

Differential Noise:

• Whining/Howling: Often indicates incorrect pinion depth or backlash. This requires professional adjustment.
• Clunking/Clicking: Could be worn spider gears, loose components, or issues with the differential carrier.
• Grinding: Suggests severe wear or damage to the gear teeth. Immediate inspection is required.

Fluid Leaks:

• Pinion Seal Leak: Replace the pinion seal. Ensure the yoke surface is smooth and free of grooves.
• Axle Seal Leak: Replace the affected axle seal.
• Cover Gasket Leak: Replace the differential cover gasket or re-seal the cover with RTV silicone.

Overheating:

• Causes: Insufficient or incorrect fluid, improper break-in, excessive load, or incorrect gear mesh.
• Solution: Check fluid, follow break-in, reduce load, or have gear mesh inspected.

For any persistent or severe issues, consult a qualified automotive technician.

8. Product Specifications

9. Warranty and Support

Warranty Information:

The Motive Gear F9-350A Ring & Pinion Set is backed by a 1 Year / 50,000 Miles warranty. This warranty covers defects in materials and workmanship under normal use. Please retain your proof of purchase for warranty claims.

Customer Support:

For technical assistance, warranty claims, or further information, please visit the official Motive Gear website or contact their customer service department.

You can also visit the Motive Gear Store on Amazon for additional products and resources.