Understanding Tyre Load Ratings in New Zealand

How to Match Load Indices, Interpret Dual Ratings, and Stay Compliant

Choosing the right tyre load rating is essential for safe driving in New Zealand — especially if you’re towing, carrying heavy loads, or operating commercial vehicles. Tyre load index and speed rating determine how much weight a tyre can safely carry and how fast it can travel without risk. In this guide, we explain how to match tyre load ratings across axles, the differences between single and dual load index tyres, and provide real-world examples for passenger cars, trailers, utes, vans, and 4WDs.

✅ What is a Tyre Load Index?

The load index is a two- or three-digit number found on the tyre’s sidewall (e.g., 91 in 205/55R16 91V). It indicates the maximum weight a tyre can carry when correctly inflated. For example:

• Load index 91 = 615 kg per tyre

• Load index 104 = 900 kg per tyre

You must always meet or exceed the vehicle manufacturer’s recommended load index. Under-loading a tyre risks heat buildup, poor handling, and potential blowouts.

✅ Load Index Rules in New Zealand

🚦 NZTA Legal Requirements:

1. Axle Matching:

   • Tyres on the same axle must be the same size and construction

   • Load index values must be within 2 points of each other

     • ✅ Example: 94 + 95 = Compliant

     • ❌ Example: 92 + 96 = Not compliant (difference of 4)

2. Front vs Rear Axles:

   • Different load ratings between front and rear are permitted

   • Each axle’s tyres must still meet the weight requirement for that axle

   • Recommended: Stay within 3 index points between axles for balanced handling

3. Speed Ratings:

   • Must match or exceed 100 km/h for road use

   • Never fit a lower speed-rated tyre than required

🔄 Matching Tyre Load Ratings Across Axles

Tyres must be evenly matched across each axle to avoid uneven braking or overloading one side:

• On a single axle, a difference of 1 or 2 load index points is allowed

• On dual-axle vehicles (e.g., trailers), match all tyres for even wear and safety

• Fitting mismatched load indices can result in a Warrant of Fitness (WoF) failure or insurance invalidation

🚛 Dual Load Index Tyres (e.g., 121/119)

Many commercial tyres show dual ratings, such as 121/119R:

• 121: Load index for single wheel use (1,450 kg per tyre)

• 119: Load index for dual wheel setups (1,360 kg per tyre)

This is critical for utes, vans, or motorhomes with dual rear wheels. The lower rating applies because each tyre shares weight with its pair and must account for one tyre losing pressure.

Always use the correct rating for your wheel configuration and never assume a tyre can carry its full single rating in a dual setup.

🚗 Passenger Cars – Load Rating Guidance

• Check your tyre placard (door frame or glovebox) for the original load index

• Always replace tyres with the same or higher load rating

• Higher load index = more reserve strength (commonly seen in XL/extra load tyres)

Example:

• A Toyota Corolla with 91V tyres requires a minimum 91 load index (615 kg) and V speed rating (240 km/h)

• Replacing with a 94V or 95W tyre is acceptable

• Replacing with an 88H would be illegal and unsafe

🧰 Vans, Light Trucks & Commercial Vehicles

These vehicles require LT (Light Truck) or C (Commercial) rated tyres:

• Common load ratings: 102, 104, 109, 113, 121

• Often come in dual-rated format (e.g., 235/65R16C 121/119R)

• Use only tyres designed for commercial loads — not passenger car tyres

Example:

• A Ford Transit might require 235/65R16C 121/119R

• Replacing with a passenger tyre (e.g., load index 95) would not be safe or legal

🎯 Trailer Tyres – Load Ratings & Safety

• Trailers must use tyres rated above their maximum expected weight

• Always calculate load per tyre and build in a safety margin (10%+)

• Use LT or “Trailer Use Only” tyres for heavy-duty trailers

• Match tyres on the same axle for consistent performance

Example:

• Single-axle trailer with 1000 kg GVM → each tyre should carry at least 550 kg (index 88)

• Tandem trailers must also have load ratings that exceed expected load per tyre

Avoid using standard car tyres on trailers unless they meet the required load rating and speed capability

🚙 Towing & Utes – What to Know

When towing with a ute or SUV:

• The rear tyres bear extra weight from the trailer’s towball load

• Many modern utes use XL or LT tyres with higher load indices

• Inflate tyres to the recommended towing pressure (often shown on a placard)

Example:

• Ford Ranger with stock 265/60R18 110T tyres

  • Load index 110 = 1060 kg per tyre

  • Towing a boat with 200 kg towball weight adds 100 kg per rear tyre

  • If carrying gear in the tray too, you may run close to capacity

  • Upgrading to index 113 or 115 gives a safety buffer

🛠 High-Load & Work Use (Tradespeople, Off-Road, Farming)

• Vehicles frequently loaded near capacity should upgrade tyre load index

• LT tyres offer tougher sidewalls, higher puncture resistance, and greater capacity

• Even for short trips, under-rated tyres can overheat or wear prematurely

Examples:

• Builder's van with 113/111 tyres should never be downgraded

• Farm utes often upgrade to 265/70R16 LT 112S all-terrain tyres for strength

• Agricultural trailers must use tyres rated for highway travel, not just field use

📊 Summary – NZ Tyre Load Rating Compliance Checklist

Final Word

Whether you’re driving a hatchback in Auckland, towing a boat in Tauranga, or hauling supplies in Te Puke, the correct tyre load rating keeps your journey safe and legal. Always match or exceed your vehicle’s required load index, ensure axles have matching tyres, and use commercial-grade tyres for high-load situations.

If you’re unsure which tyre is right for your vehicle or towing setup, contact the Tyre Dispatch team — we’re locally owned and operated Kiwis, and we’re here to help you drive safely, with confidence.