How to Check Your Car's Towing Capacity

Before towing anything, you need to know your vehicle's exact towing capacity. Here's how to find this information and understand what it means.

Where to Find Your Towing Capacity

1. The VIN Plate (Most Reliable)

The VIN plate (or compliance plate) is usually located:

• Inside the driver's door frame
• Under the bonnet on the bulkhead
• On the driver's side of the dashboard (visible through windscreen)

The plate typically shows:

• Line 1: Gross Vehicle Weight (maximum laden weight of vehicle)
• Line 2: Gross Train Weight (vehicle + trailer maximum)
• Line 3: Maximum front axle weight
• Line 4: Maximum rear axle weight

To calculate your maximum trailer weight from the VIN plate:

Gross Train Weight - Gross Vehicle Weight = Maximum Trailer Weight

2. Your V5C Registration Document

Section G of your V5C shows:

• Technically Permissible Maximum Towable Mass (braked): This is your braked towing capacity

This figure should match or be lower than what the VIN plate calculation gives you.

3. Owner's Manual

Your vehicle handbook contains detailed towing specifications including:

• Braked towing capacity
• Unbraked towing capacity
• Maximum noseweight
• Roof load while towing
• Special requirements or restrictions

4. Manufacturer's Website

Most manufacturers publish technical specifications online. Search for your exact model, year, and engine variant as capacities vary.

5. Online Databases

Sites like Parkers, What Car?, and manufacturer forums have towing capacity data for most vehicles.

Understanding the Numbers

Braked Towing Capacity

The maximum weight you can tow when the trailer has its own braking system (override or electric brakes). This is the figure most people need.

Unbraked Towing Capacity

Maximum weight for trailers without brakes. Legally capped at 750kg in the UK, but your vehicle may have a lower limit.

Maximum Noseweight

The maximum downward force on the towball. Typically 50-100kg. This limits how you can load your trailer.

Gross Train Weight

The absolute maximum combined weight of vehicle + trailer + all contents and passengers. Even if your towing capacity is high, GTW may limit you.

Factors That Affect Towing Capacity

Engine and Transmission

• Same model can have different capacities with different engines
• Manual vs automatic may have different ratings
• 4x4 variants often have higher capacity than 2WD

Vehicle Specification

• Tow pack or towing preparation option may increase capacity
• Air suspension models may have different limits
• Some options add weight, reducing payload and towing capacity

Year of Manufacture

• Same model may have different capacities across model years
• Facelifts often bring specification changes

A Worked Example

Let's say your VIN plate shows:

• Gross Vehicle Weight: 2,200kg
• Gross Train Weight: 4,400kg

Calculation: 4,400 - 2,200 = 2,200kg maximum trailer weight

But wait - check your V5C. If it shows "Maximum Towable Mass Braked: 2,000kg", then 2,000kg is your limit (the lower figure applies).

What About the 85% Rule?

Your legal towing capacity may be higher than what's recommended for safe, stable towing:

• For novice towers: Keep trailer weight below 85% of your car's kerb weight
• Example: 1,500kg kerb weight × 0.85 = 1,275kg recommended maximum trailer

This isn't a legal requirement, but it provides a safety margin for handling emergencies and crosswinds.

Checking a Specific Trailer/Caravan

Once you know your capacity, check it against:

1. Trailer MAM (Maximum Authorised Mass): The maximum the trailer can legally weigh when loaded
2. Your planned load: Calculate actual loaded weight
3. GTW limit: Add your loaded vehicle weight to loaded trailer weight

Common Mistakes to Avoid

Using the Wrong Figure

• Don't use braked capacity for an unbraked trailer
• Don't forget to account for your vehicle's load (passengers, luggage)
• Don't assume your towbar is rated to your vehicle's maximum

Ignoring GTW

You might have a 2,500kg towing capacity, but if GTW is 4,000kg and your vehicle weighs 2,000kg loaded, you can only tow 2,000kg.

Overlooking Noseweight

An incorrectly loaded trailer might be within your towing capacity but exceed your noseweight limit, causing handling problems.

If In Doubt

• Contact your vehicle manufacturer directly
• Ask a franchised dealer to check their system
• Use a public weighbridge to check actual weights
• Consult a professional towbar fitter

Quick Reference Checklist

1. Find your braked towing capacity (VIN plate, V5C, or handbook)
2. Check your gross train weight limit
3. Note your maximum noseweight
4. Consider the 85% rule for safe towing
5. Verify your towbar is rated for your intended use