Quick Answer

A TPMS warning on the highway is often triggered by:

• Normal pressure increase from tyre heat
• A slow leak becoming noticeable at speed
• Temperature rise during long-distance driving
• Incorrect baseline pressure settings
• Signal drop or sensor fault

1. Heat and Pressure Expansion (Normal Behaviour)

When driving at highway speeds, tyres heat up. As temperature increases, the air inside expands and pressure rises. This is normal.

It’s common to see a 2–6 PSI increase during sustained highway driving. If your high-pressure alert is set too low, the system may trigger a warning even though the tyre is behaving normally.

Learn more about how sensors work: How Does a TPMS Sensor Work?

2. A Slow Leak Becomes Obvious at Speed

At low speeds, a small puncture may not trigger an alert. On the highway, pressure changes can accelerate and the drop becomes noticeable.

If your TPMS shows one tyre dropping steadily while others remain stable, pull over safely and inspect that tyre.

3. Excessive Heat Build-Up

High temperature alerts may indicate:

• Underinflated tyres
• Heavy loads or towing
• Long-distance driving in hot conditions
• Brake drag or bearing issues

Heat is often an early warning sign of tyre stress. For towing advice: Best TPMS for Caravans & Towing

4. Alert Thresholds Set Too Tight

Many drivers set their low and high pressure alerts too close to their baseline. On the highway, normal fluctuations can then trigger warnings.

A common guideline:

• Low-pressure alert: 10–15% below baseline
• High-pressure alert: 20–25% above baseline

5. Signal Loss or Sensor Fault

If the alert is inconsistent or disappears after slowing down, it may be a communication issue rather than a tyre problem.

Troubleshooting help: TPMS Sensor Not Reading?

When Should You Pull Over Immediately?

Stop safely if:

• Pressure drops rapidly
• One tyre falls significantly below others
• Temperature rises sharply and continues climbing
• You feel vibration or handling changes

Early action prevents tyre destruction and potential blowouts.

How to Prevent Highway TPMS Alerts

• Check cold tyre pressures before long drives
• Set sensible alert thresholds
• Monitor trends rather than reacting to small fluctuations
• Use temperature monitoring when towing

Monitoring Tyres Safely on the Highway

A reliable TPMS helps you distinguish between normal heat expansion and genuine tyre failure risk.

View the Safety Sam system here: Tyre Pressure Monitoring System

Frequently Asked Questions

Is it normal for tyre pressure to increase on the highway?

Yes. Pressure typically increases as tyres heat up during sustained driving. This is normal unless the rise is extreme or uneven.

Why does my TPMS only go off at high speeds?

Higher speeds generate more heat and can reveal slow leaks that aren’t noticeable at low speeds.

Can a TPMS give false alarms?

Alerts can occur if thresholds are set too tight or if there’s a sensor communication issue.