Weight Distribution for Campervan Conversions: The Ultimate Guide

Understanding Weight Distribution for Campervan Conversions

Understanding weights and weight distribution might not be the most exciting topic in vanlife, but it's a critical one that deserves attention. Weights affect not only safety but also how your campervan performs and handles on the road. Improper management can pose risks to both you and other road users, as well as shorten the lifespan of your vehicle and its components. Overloading can also result in the vehicle not meeting legal requirements and safety standards.

Let’s start by explaining all the abbreviations and terms (GVWR, GAWR, etc.) and then go through a weight distribution example from our own conversions as practical examples.

1._Understanding Weight Specifications

In this section, we explain important terms and concepts related to vehicle weights and campervan conversions, such as kerb weight, payload, gross vehicle weight (GVW), and how to calculate the gross vehicle weight rating (GVWR).

Understanding these terms is essential for safely and legally converting your van, especially if you want to stay within legal weight limits in countries like the UK, Sweden, Denmark, and Germany.

2._Impact of Weight in Brief

Here, we explore how weight affects more than just fuel consumption and brake wear. Weight has a direct impact on the safety, performance, and durability of your campervan.

We also discuss common misconceptions, such as the belief that you can increase the GVWR through aftermarket upgrades, and how weight distribution affects the vehicle's centre of gravity and handling.

3._Your Role as a DIY Builder

As a DIY builder, it’s important to monitor your vehicle’s weight from start to finish. This includes keeping track of the kerb weight, payload, and ensuring you do not exceed the manufacturer's weight limits.

We also cover how to think about weight distribution during your build process to avoid instability and other safety issues while on the road.

1. Understanding Weight Specifications

1.1 Glossary

• Kerb Weight: The weight of the vehicle when it's empty, including standard equipment, oils, lubricants, and a full tank of fuel. The driver, passengers, or additional equipment are not included.

• Payload: The weight added to the vehicle's kerb weight, including the driver, passengers, additional equipment, conversion weight (permanent), and the weight of the load (movable).

• Gross Vehicle Weight (GVW): The sum of the kerb weight and the payload. Includes everything from the vehicle and its equipment to the driver, passengers, and all cargo.

• Gross Vehicle Weight Rating (GVWR): The maximum allowed total weight for the vehicle. The GVW must never exceed the GVWR.

• Axle Weight (GAW): The weight distributed on each axle, front and rear.

• Gross Axle Weight Rating (GAWR): The maximum allowable weight for a single axle.

• Centre of Gravity (CG): An imaginary point where all weight is concentrated, affecting the vehicle's stability and balance.

1.2 Resources

For more information on weights and specifications, refer to technical specifications from manufacturers like Ford Transit, Mercedes Sprinter, and Ram ProMaster. Specifications may vary between different models and years.

3. Your Role as a DIY Builder

As a DIY builder, it’s your responsibility to keep the vehicle’s weight within the specifications set by the manufacturer (GVWR and GAWR). Here are some steps to keep weights under control:

• Check the kerb weight specified in the vehicle's specifications, and weigh the vehicle after conversion to check the gross weight.

• Plan the layout carefully: Distribute weight as evenly as possible between the front and rear axles and the left and right sides.

• Use lightweight materials where possible to minimize the total weight.

• Keep the vertical centre of gravity low: Place heavy components like batteries and water tanks as close to the floor as possible.
  

4. Weight Breakdown of Our Campervans

Here are examples of weight breakdowns for two of our previous campervan conversions, including Ford Transit and other brands, with detailed information on kerb weight, payload, and gross weight.

2. Impact of Weight in Brief

2.1 Weight

Many people think of weight in terms of fuel consumption, brake wear, and suspension performance, but it’s much more than that. Weight specifications like GVWR and GAWR affect the safety, durability, and behaviour of the vehicle on the road. These values are determined by the manufacturer through standardized tests including braking, stability, chassis durability, and driving dynamics.

A common misconception is that the GVWR can be increased through aftermarket upgrades (e.g., suspension upgrades), which is not true. GVWR depends on several factors and cannot be changed.

2.2 Gross Vehicle Weight

The gross vehicle weight is the sum of:

• The vehicle's kerb weight

• Passengers (the estimated weight of the maximum number of people the vehicle is designed for, except for the driver who is included in the kerb weight)

• Cargo (the maximum amount of cargo the vehicle is designed to carry)

2.3 Weight Distribution

Weight distribution affects the vehicle's centre of gravity and thus its stability and handling:

• Horizontal Centre of Gravity: Affects weight distribution between the front and rear axles, steering, and traction.

• Vertical Centre of Gravity: Affects brake dive and cornering roll.

• Lateral Centre of Gravity: Affects weight on the left and right sides and the vehicle’s stability in corners.
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2.4 Trailer Gross Weight

The gross weight of a trailer is the sum of:

• The trailer's kerb weight

• Passengers (the estimated weight of the maximum number of people the vehicle is designed for)

• Cargo (the maximum amount of cargo the trailer is designed to carry)

5. Further Reading

Here are the sources used if you want to read further:

• Swedish guidelines on weights and load (Transportstyrelsen.se)

• The role of GVWR and CGWR in specifying work vehicles (ntea.com)

• Calculating weight distribution and load capacity for commercial vehicles simply (worktruckonline.com)

• Consequences of reclassifying a vehicle's GVWR and GAWR (forconstructionpros.com)

• Guidelines for trailer/towing capacity (curtmfg.com)

• General database for finding information about your car (car.info)