Increasing a caravan’s payload with AL-KO
Would you like to install additional equipment such as an air conditioning system, a manoeuvring system or a hydraulic support system on your caravan? Would you like to take your e-bikes with you on your camping trip, or do you otherwise need more payload on your camping trip? Is your caravan a real collector's item that you absolutely love, but you need more load capacity now?&npsp; There are many reasons to want to increase a caravan’s payload, but the goal is always the same: to be able to carry more weight in your vehicle. Because, as we all know, every kilo counts when camping. By increasing the payload, you increase your caravan’s permissible gross weight – i.e. how heavy it is allowed to be including its load on the road.
NB: For any weight increase, two parties have a say. On the one hand, AL-KO as the chassis manufacturer will inform you what the body is technically able to bear. On the other side, your caravan’s manufacturer must approve how much payload increase the body can take on a day-to-day basis. Further information on this can be found in the section "Necessary documents for a payload increase".
The payload is calculated from the difference between the maximum authorised mass and the unladen weight: Maximum authorised mass – unladen weight = payload
Since the unladen mass stated in the Certificate of Approval does not always correspond to the actual unladen weight, it is always advisable to go to a weighbridge beforehand. If your caravan has an AL-KO chassis – which is what almost all manufacturers use today – we can offer you bespoke solutions and options to load more weight onto your caravan so you can set off on your holiday stress-free. In this guide, you will learn the basics about what steps can be taken and their respective requirements.
How does a payload increase work? Variants and requirements for more payload
There are numerous ways to achieve the desired weight increase – but not all variants are possible for every caravan. Which remedies are suitable is determined by the interaction of the caravan’s current weight, the desired additional weight and the configuration of the body components. As a general rule, however, the greater the difference between the current and the target permissible gross weight, the more components or body components will have to be replaced. For this reason, the costs for the various types of payload increase can differ considerably from each other and they can even vary greatly for the same type of payload increase depending on the initial situation.
In order for us to be able to determine which procedure will lead to the desired outcome for your caravan, we start every enquiry with the checklist for increasing the weight of AL-KO chassis. This is the basic prerequisite for further consultation and forms the basis for all further steps to increase your caravan’s gross weight.
In this checklist, you fill in the essential technical data about your caravan. Our team of experts will then use this information to determine which of your caravan’s components can already carry the desired higher load and which need to be upgraded.
We require the following information from you:
- Caravan manufacturer
- Caravan type/caravan model
- Vehicle identification number
- Chassis drawing number (chassis number)
- Data on permit and weight
- Vehicle manufacturer's approval (clearance certificate)
- Technical data on axle, wheel brake, overrun device, towing connection, tyre size
Why is the checklist so important? AL-KO as a chassis manufacturer cannot tell what individual components and their respective technical features your caravan has just from your caravan type. However, this information is essential to resolve the issue of your caravan’s weight and how to increase its payload. The interaction of the components is decisive for the type of the payload increase that can be considered for your individual vehicle.
Weight plate upgrade
For some caravans, there is the possibility of a so-called weight plate upgrade. This is a payload increase that only takes place on paper – namely in the vehicle registration document. This modification does not require any technical adjustments to the chassis, but is carried out exclusively by the caravan manufacturer. The manufacturer only checks the gross weight for which your caravan’s body is actually designed. This is confirmed with a clearance certificate and a new type plate. Then you take the caravan to a testing organisation such as TÜV or DEKRA for inspection and acceptance, and finally have the new permissible gross weight entered in the vehicle documents at the vehicle registration office.
Disadvantages: This type of payload increase only applies in rare cases and usually only achieves a small increase in weight or payload.
The costs for a weight plate upgrade start at approx. €150, depending on whether a brake calculation from the chassis manufacturer is also required.
Replacing the suspension elements in the axles
First, the basics of axle suspension: If the caravan has to bear more weight, the axles are the first to take it. The caravan’s axle tubes contain the suspensions, which consist of round rubber cords. There are three round rubber cords per axle side in each axle. These have different lengths and degrees of hardness depending on the type of caravan. If more weight presses on the axles than they were designed to bear, the rubber round cords will deform and become oval over time and the axle link will then sit crooked in the axle tube. The visible consequence of overloading is worn tyres on the outside, which can subsequently lead to a tyre blowout. Not a great idea!
In order to relieve overloaded axles and the resulting damage or to avoid it in the first place, we are happy to check whether replacing the suspension elements with a stronger version could be an option for you.
With this form of weight increase, the caravan’s axles are removed and the round rubber cords are taken out. Our experts calculate which length and degree of hardness the new round rubber cords must have in accordance with the desired weight increase in order to bear the increased axle load. After the professional installation of the axle rubbers, the track and camber are correctly adjusted. With this type of payload increase, a maximum weight increase of 200 kilograms can be achieved.
Hardness of plastics and elastomers
Hardness is the mechanical resistance of a wear material to the mechanical penetration of another body. The hardness of elastomers and plastics is measured using the Shore Hardness scale, named after Albert Ferdinand Shore, an American metallurgist. The scale ranges from 0 to 100 Shore – the greater the Shore hardness, the harder the material, in this case the round rubber cords.
The price for a payload increase by replacing the axle rubbers is around €500 on average. If a more complex installation situation prevails (e.g. manoeuvring system, complex cable feed-throughs or similar), higher costs may be incurred.
Replacing chassis components
Depending on the individual situation and desired weight, a payload increase may require the chassis components to be replaced. This may include the complete axle(s), brakes, shock absorbers, the overrun device or frame parts. We will also determine which of your caravan’s components can already bear the desired additional weight and which need to be replaced in this case using the checklist.
In addition to the information compiled using the checklist, additional factors have to be checked for this type of payload increase: These include, for example, the presence of a GRP (glass-fibre reinforced plastic) floor, a stabiliser coupling, an ATC or manoeuvring system, as well as the load-bearing capacity of tyres and rims, the space available in the wheel arch or a 100 km/h approval, as these additional features also have an impact on the ultimate interaction of all components. AL-KO reserves the right to carry out payload increases exclusively in its own customer centres.
By replacing the corresponding chassis components, the permissible gross weight can be increased by a maximum of 300 kilograms.
The base price for this form of payload increase starts at €1,800, but the individual combination of components is decisive for each body. This means costs can range quite extensively above this base price.
Replacing the entire chassis
To increase your caravan’s permissible gross weight, it may also be necessary to replace the entire chassis. This is the case when replacing individual components will not provide any significant increase in weight. As with the replacement of chassis components, the various equipment features are also checked here (GRP floor, stabiliser coupling, ATC, manoeuvring aid, etc.).
When replacing the chassis, the existing chassis is separated from the body in its entirety and replaced by a new one that can carry the intended load. Replacing the entire chassis can result in a maximum payload increase of 500 kilograms.
The starting price for the replacement of the chassis is €5,800 and again depends heavily on the individual conditions.
Overview of the different types and costs of payload increase
- Weight plate upgrade, potential payload increase of 100 to 200 kg, costs around €180
- Replacement of suspension rubbers, potential payload increase of 100 to 200 kg, costs around €500
- Replacement of chassis components, potential payload increase of 100 to 200 kg, costs around €1800
- Replacement of complete body, potential payload increase of 100 to 200 kg, costs around €4800
Necessary documents for a payload increase
Now you know what payload increase options can generally be considered. If you haven’t done so already, you should contact your caravan’s manufacturer now to clarify how much additional weight can be approved for your model.
You apply for a so-called clearance certificate for this. With this, the manufacturer confirms that the caravan body is also designed for the new, higher permissible gross weight after the payload increase and is suitable for the European market. In addition, the caravan’s type plate must be renewed in almost all cases – this is also issued by the manufacturer with the new information.
On the one hand, these documents are necessary for the implementation of the payload increase at AL-KO; on the other hand they are mandatory for the subsequent acceptance of the payload increase by an appropriate vehicle inspection authority, for example TÜV or DEKRA. As a final step, you must have the new weight information entered in the vehicle documents (vehicle registration document) by the vehicle registration office.
What else should be considered when increasing your payload
Initially only the permissible gross weight of your caravan changes after a payload increase – but this in turn affects the entire vehicle combination.
- Towing vehicle: Please also check whether your towing vehicle is designed for the future weight of your caravan.
- Speed limit: The caravan’s increased weight may result in the loss of the 100 km/h approval if the trailer is heavier than the towing vehicle following the payload increase. This would mean being limited to a speed of 80 km/h on German motorways. Other countries may apply different speed limits and regulations.
- Driving licence: Check your existing driving licence category. If your vehicle combination exceeds a gross weight of 3.5 tonnes following the payload increase, you must upgrade to at least category B+E.
Frequently Asked Questions (FAQs) about payload increases
How much does it cost to increase a caravan’s payload? Is there a flat rate offer?
It is not possible to give a flat rate for the costs of a payload increase. That’s because each caravan is different. The interaction of all the components in your caravan decides what type of payload increase is possible and the resulting costs, which makes it impossible to offer a flat rate. That’s why the checklist is essential when calculating the payload increase.
Can you retrospectively increase a caravan’s payload?
Yes, this is possible with many models. Once again, the deciding factor is your vehicle’s specific initial situation, which we determine using our checklist.
Who carries out a payload increase?
A caravan payload increase is usually carried out by the chassis manufacturer after checking the respective vehicle’s requirements. An exception to this is the weight plate upgrade, which does not require any technical changes. This is simply approved by the TÜV and then entered in the vehicle documents at the vehicle registration office.
Where can I go to get my caravan’s payload increased?
AL-KO reserves the right to carry out payload increases exclusively in its own customer centres. As a chassis manufacturer, we offer comprehensive expertise and can professionally and appropriately assess which individual solutions are available for each chassis. We can also call on the full expertise of our Development department in the event of unexpected problems and have access to special technical facilities.
How long does a payload increase process take from enquiry to completion?
The time required may vary as much as the cost. We determine which components will need to be replaced depending on the type of payload increase required to achieve your desired weight. The delivery time of these components is an important factor in the entire process, and we have no influence over this. Therefore, we would strongly recommend that you do not arrange for the payload to be increased shortly before you plan to go on holiday. However, we assure you that we will carry out the entire process as efficiently as possible.
Can I increase the permissible gross weight of my caravan indefinitely?
No, unfortunately this is not possible, as at some point the body would no longer be able to withstand the weight. The manufacturer of your caravan will tell you how much additional weight can be approved for your model.
Podcast on the theme of "Caravan payload increases”
Michael Duckek manages the customer centre at the Kötz site and knows his stuff when it comes to the subject of payload increases. That's exactly why he was a guest on our partner CamperStyle’s podcast. In the episode "Caravan payload increases", Michael helps to answer questions about caravan payload increases. Listen now!