A Central Tire Inflation System (CTIS) lets a vehicle change tire pressure while driving, either automatically or at the driver’s command. The goal is to boost traction, cut fuel consumption, extend tire life, and adapt to changing surfaces. You’ll see CTIS on military platforms, 4x4 off-roaders, ag and forestry machines, heavy trucks and buses, and mining/construction vehicles.

How It Works (Plainly)

Control unit: In-cab, the driver selects a surface (paved, mud, sand, snow) or a target psi/bar.

Manifold & valves: Add or vent air to each tire to hit the setpoint.

Compressor/reservoir: Supplies air when needed.

Rotary unions: Feed air to rotating wheels with leak-tight sealing.

Pressure sensors: Continuous feedback for precise regulation.

Why It Matters: 6 Key Benefits

Traction & mobility: Lower pressure widens the footprint; better on sand, mud, and snow with less wheelspin.

Fuel efficiency: Correct highway pressure cuts rolling resistance.

Tire life: Even wear and lower shoulder heat slow degradation.

Ride & load care: Pressure tuning damps vibration; cargo stability improves.

Safety: Over/under-pressure alerts; limited run-flat assistance via compensating inflation.

Uptime: Switch road↔terrain pressures without stopping.

Core Components

ECU & driver panel

Pressure/temperature-compensated sensors

Fast solenoid valves & manifold

Air compressor and tank

Rotary unions and lines

Safety/one-way valves

Use Cases

Road → site transitions: Drop pressure for the jobsite, restore for pavement.

Heavy loads / delicate ground: Farms, forests, mines.

Bad weather: Snow/Mud modes enlarge contact patch.

Long-haul fleets: Standardized pressures lower fuel and tire cost per km.

Pros / Cons at a Glance

Pros: Adaptive pressure, better traction, potential fuel savings, longer tire life, smoother ride, faster ops.

Cons: Upfront cost, install complexity, ongoing maintenance, added mass.

Care & Correct Use

Weekly visual checks: Hoses, fittings, leaks.

Dryer & filter service: Protects compressor and air lines.

Right mode for speed/surface: Follow OEM psi/bar ranges.

Tire compatibility: Load index and sidewall flex must match manufacturer limits.

Calibration: Re-check after seasonal or load changes.

Buying Checklist

Vehicle fitment: Axle/bolt pattern, hub/joint style.

Capacity: Compressor flow (L/min) and time-to-pressure.

Preset profiles: Sand/Mud/Snow/Highway, speed-pressure interlocks.

Service network & spares: Access to rotary unions and valves.

Warranty & TCO: Validate payback via fuel/tire savings.

FAQ – Short Answers

Is CTIS legal? Generally yes—follow OEM guidance and traffic standards.

Will it harm tires? Not when used within spec; wrong pressure accelerates wear.

With run-flat tires? Possible, but confirm system compatibility and goals.

City use? Proper pressure helps comfort and economy in stop-go traffic.

In short: CTIS dynamically optimizes pressure for the surface and load to deliver measurable gains in performance, safety, and cost.