Excavator Final Drive Installation: A Complete Step-by-Step Guide

Introduction

Paying a dealer $500-$1,000 for final drive installation labor? With basic mechanical skills and the right tools, you can replace an excavator final drive yourself in 4-6 hours. This guide walks you through every step.

⚠️ Safety First: Always work on level ground with the machine properly supported. Never work under an unsupported excavator.

Tools You'll Need

• Socket set (metric, up to 36mm)

• Torque wrench (capable of 300+ Nm)

• Impact wrench (recommended for bolt removal)

• Hydraulic jack or engine hoist (final drives weigh 80-200 kg)

• Clean containers for gear oil

• New gear oil (check your machine's spec)

• Thread locker (medium strength)

• Shop rags and degreaser

Step 1: Prepare the Machine

1. Park on flat, solid ground

2. Lower all attachments to the ground

3. Engage the safety lock

4. Release hydraulic pressure (operate all controls with engine off)

5. Disconnect the battery

Step 2: Remove the Track (if needed)

On most excavators, you can access the final drive without fully removing the track, but you'll need to:

1. Release track tension by loosening the grease fitting

2. Remove the sprocket guard if present

3. Slide the track off the sprocket

Step 3: Drain the Gear Oil

Place a container under the final drive drain plug. Remove the fill plug first (to allow air in), then the drain plug. Let it drain completely. Inspect the drained oil for metal particles.

Step 4: Disconnect Hydraulic Lines

1. Clean around all hydraulic fittings thoroughly

2. Label each hose and its port (take photos!)

3. Cap all open hydraulic lines immediately to prevent contamination

4. Cap the motor ports on the final drive

Step 5: Remove the Old Final Drive

1. Support the final drive with a jack or hoist — these are heavy!

2. Remove all mounting bolts (typically 16-20 bolts)

3. Carefully separate the final drive from the track frame

4. Clean the mounting surface thoroughly

Step 6: Install the New Final Drive

1. Apply anti-seize compound to the mounting surface

2. Position the new final drive on the track frame

3. Insert all mounting bolts hand-tight, then torque in a cross pattern

4. Reconnect hydraulic lines to matching labeled ports

5. Reinstall the track and tension it properly

Step 7: Fill with Gear Oil

1. Fill through the upper port until oil reaches the check plug level

2. Use the manufacturer-specified gear oil (typically 80W-90 or TO10)

3. Replace both fill and check plugs

Step 8: Post-Installation Checks

1. Start the engine and let it idle for 5 minutes

2. Cycle all hydraulic functions to purge air

3. Slowly operate the track in both directions

4. Listen for unusual noises

5. Check for leaks at all fittings

6. Re-check mounting bolt torque after 8 hours of operation

Common Installation Mistakes to Avoid

• ❌ Forgetting to cap hydraulic lines → contamination destroys the new final drive

• ❌ Uneven bolt torque → causes oil leaks and premature wear

• ❌ Wrong gear oil → check your manual for the correct specification

• ❌ Not purging air from the hydraulic system → erratic track movement

Watch Our Installation Videos

Check out our video library for real installation demonstrations on CAT, Komatsu, and Hitachi models.

Order your replacement final drive today →