How to Care for a Vehicle With Over 100K Miles

Modern vehicles routinely surpass 100,000 miles with proper maintenance.  At Borst Automotive, we’ve helped countless vehicles reach 100,000 miles and beyond. Here’s your guide to high-mileage vehicle care.

Essential Maintenance Items

The timing belt or chain is critical at high mileage.  Belt-driven engines require replacement every 60,000-100,000 miles as failure can lead to catastrophic engine damage.  Chain-driven engines need their tensioners and guides inspected, as failure can cause similar damage.  Listen for rattling sounds from the timing cover area, especially during cold starts.

Transmission service becomes vital beyond 100,000 miles.  Traditional automatic transmissions need fluid and filter changes every 50,000 miles.  Modern dual-clutch and CVT transmissions often require specialized service procedures after the fluid has been replaced.  Warning signs to watch out for include delayed engagement, harsh shifting, or unusual noises. 

Suspension components face significant wear by this mileage.  Struts and shocks often fail gradually, causing excessive bounce, uneven tire wear, and poor handling.  Ball joints, crucial for steering and wheel alignment, show wear through clunking sounds or steering wandering.  Control arms with integrated bushings frequently need replacement as well. Common symptoms include:

• Steering wheel vibration
• Uneven tire wear patterns
• Clunking over bumps
• Vehicle pulling to one side
• Tire feathering on edges

Worn suspension components tend to go unnoticed due to the gradual nature of their deterioration, but replacing worn components dramatically improves safety and handling.  We recommend addressing suspension issues promptly as they affect tire life and other components.

Fluid Maintenance

Oil changes become increasingly important in high-mileage engines.  Consider switching to high-mileage specific oil and reducing change intervals to 4,000 miles.

Coolant requires complete replacement to prevent corrosion and maintain proper engine temperature.  Power steering fluid often darkens and requires changing to prevent pump wear.  Brake fluid absorbs moisture over time, necessitating replacement every 2 years.

Common Wear Points

Engine and transmission mounts deteriorate significantly after 100,000 miles.  These rubber-based components soften and crack, leading to excessive engine movement.  Signs include vibration at idle, clunking during gear changes, and increased cabin noise.  Regular inspection can catch mount failure before it affects other components.

Gaskets and seals begin showing their age through various leaks.  Valve cover gaskets often seep oil onto the exhaust manifold, creating burning smells.  Timing cover seals can slowly drip oil, leading to low oil levels and potential belt contamination.  Main seals, both front and rear, become brittle and can allow significant oil leaks.  Oil pan gaskets frequently fail from road debris impact and general aging.

Interior components also show wear.  Seat bolsters crack and flatten, weatherstripping loses its seal, and door hinges can sag.  Window regulators may operate slowly or bind, and power seat motors often struggle.  These issues, while not critical to vehicle operation, affect comfort and value.

Preventive Care

Schedule regular inspection appointments (at least annually) with your service advisor at Borst Automotive. Document all services and keep detailed records of repairs. Address unusual sounds, smells, or behavior immediately.  

Warning signs to monitor:

• Increased oil consumption
• New vibrations
• Fluid leaks
• Changes in engine sound
• Delayed transmission engagement

Preventive maintenance costs less than emergency repairs. Choose quality parts as they last longer and protect other components. Consider updated or improved replacement parts when available.

Maintain a repair fund for inevitable wear items. Follow manufacturer-recommended service intervals, adjusting for severe conditions like extreme temperatures or frequent short trips.

Preventive Maintenance & Care at Borst Automotive

Trust Borst Automotive to help maintain your high-mileage vehicle. Schedule an inspection at one of our convenient locations in Tucson, Phoenix, Mesa or Cataline today to ensure many more miles of reliable service.