120k Mile Maintenance Checklist
A comprehensive 120,000-mile maintenance guide to ensure high-mileage vehicle reliability, covering critical fluids, timing components, suspension, and long-term wear items.
Overview
Summary and key details for this checklist.
At 120,000 miles, your vehicle has likely completed its second or third major maintenance cycle. This interval is vital because many 'lifetime' components or long-life fluids are finally due for replacement. Neglecting this stage can lead to catastrophic engine failure or expensive drivetrain repairs.
For a DIY enthusiast, this checklist may take 4 to 8 hours depending on the complexity of the tasks attempted. A professional shop will typically require a full day to perform a complete 'Level 3' inspection and service. Budgeting for both time and parts is essential for this high-mileage milestone.
Printable Checklist
A clean, scannable checklist view. (You can export/print from the sidebar.)
| Item | Priority | Who | Time | What to check (Pass/Fail) | If failed (Next step) |
|---|---|---|---|---|---|
| Engine Oil & Filter | Required | Shop/DIY | 30 min | Clean oil at correct level | Change oil and filter |
| Engine Coolant Flush | Required | Shop/DIY | 60 min | Correct pH/color; no debris | Flush and refill system |
| Transmission Fluid | Required | Shop | 60 min | No burnt smell; correct level | Drain and fill or flush |
| Spark Plug Replacement | Required | Shop/DIY | 45-90 min | No heavy carbon or electrode wear | Replace all plugs |
| Timing Belt (if equipped) | Required | Shop | 4-6 hrs | No cracks, fraying, or oil soak | Replace belt and water pump |
| Serpentine/Drive Belts | Required | DIY | 20 min | No glazing or deep cracks | Replace belt |
| Brake Fluid Condition | Required | Shop/DIY | 45 min | Clear/amber; low moisture % | Flush brake system |
| Brake Pads & Rotors | Required | Shop/DIY | 45 min | >3mm pad thickness; no warping | Replace pads/resurface rotors |
| Tire Tread & Pressure | Required | DIY | 15 min | >4/32" tread; even wear | Rotate or replace tires |
| Suspension Bushings | Recommended | Shop | 30 min | No tearing or missing rubber | Replace control arms/bushings |
| Shock Absorbers/Struts | Recommended | Shop | 20 min | No visible oil leaks; no bouncing | Replace in pairs |
| Battery Health Test | Required | DIY | 10 min | 12.6V+; no terminal corrosion | Clean terminals or replace |
| Engine Air Filter | Required | DIY | 5 min | Filter is white/grey; no debris | Replace filter |
| Cabin Air Filter | Recommended | DIY | 10 min | No mold smell; clean pleats | Replace filter |
| Differential/Transfer Case | Recommended | Shop | 45 min | Fluid level full; no leaks | Change gear oil |
| Fuel Filter (External) | Optional | Shop/DIY | 30 min | No restriction in fuel flow | Replace filter |
| PCV Valve | Recommended | DIY | 15 min | Valve rattles when shaken | Replace valve |
| Wheel Bearings | Recommended | Shop | 20 min | No humming or play in wheel | Replace hub assembly |
| Exhaust System | Recommended | DIY | 15 min | No holes, rust, or loose hangers | Patch or replace sections |
| Wiper Blades | Required | DIY | 5 min | No streaking or torn rubber | Replace blades |
Use this table to track your progress. We recommend performing the 'Required' items first to ensure the vehicle is safe and mechanically sound. Items marked as 'Shop' often require specialized equipment like a lift or pressurized fluid exchangers.
Keep a physical copy of this checklist in your glovebox once completed. Documenting the date and mileage of these services significantly increases the resale value of your vehicle and helps you track long-term wear patterns.
Notes
Extra context, cautions, and helpful tips.
After completing your 120,000-mile service, it is important to monitor the vehicle closely for the next 100 miles to ensure no leaks or loose components were missed.
- Always dispose of used oil and coolant at an authorized recycling center.
- Reset your 'Maintenance Required' light using the dashboard sequence.
- Check for any active recalls using your VIN on the NHTSA website.
- Listen for new noises after changing belts or suspension components.
- Re-torque wheel lug nuts after 50 miles if tires were removed.
- Clean the engine bay with a mild degreaser to make future leak detection easier.
- Update your vehicle's service logbook with receipts for parts.
- Browse similar checklists for Inspections or Tires.
Related Checklists
More checklists with similar tags (mileage, interval, season, tasks).
FAQ
Common questions about this checklist.
Start from the complete car maintenance checklist, then narrow down by mileage, interval, and season.