AL-KO Caravan Chassis Handbook User Manual

							CARAVAN CHASSIS
HANDBOOK FOR VEHICLES ON 
THE AL-KO CARAVAN CHASSIS 
						

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GENERAL INFORMATION
The AL-KO lightweight chassis has been perfected by 
many years of research and development, supported by an 
exhaustive test programme. 
Manufactured from high quality steel, the chassis has extra 
deep sections to provide strength at points of maximum 
stress. Large elongated holes are punched in the longitudinal 
chassis members, to reduce weight to a minimum. Each hole 
incorporates a return flange to maintain the required strength 
and provide rigidity in the extra deep sections. 
The chassis frame is of a bolted construction which allows 
replacement of individual parts should the need arise.
AL-KO Chassis and axles are manufactured with the fixing 
positions for a range of chassis accessories already included. 
Some of these accessories are included as standard from the 
vehicle manufacturer and are positioned for correct and safe 
usage of these products. 
For further details on the range of accessory products that 
can be fitted and used with the AL-KO Chassis, please refer 
to the Accessories section at the rear of this document, 
pages 37 - 43.
AL-KO CARAVAN CHASSIS
AL-KO does not recommend the removal of standard fit accessory 
products to allow fitment of third party products and cannot be 
held responsible should the removal and subsequent fitment of 
third party products causes damage to the chassis components.  
The process of fitting third party products to the AL-KO Chassis 
therefore may invalidate the chassis warranty.  
						

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HOT DIP GALVANISATION
The chassis is Hot Dipped Galvanised. This is regarded as one 
of the best forms of corrosion protection. It does however 
require minimal maintenance in certain circumstances. 
When new, the chassis is of a bright and shiny appearance. 
As the galvanising cures during the initial 2/ 3 month 
period, this will gradually change to a medium/dark grey 
colour. This grey finish is the ideal, giving the correct 
protective coating. During this curing period the surface 
should be protected to avoid possible wet storage stain, 
in the form of a soft, light coloured, porous, oxidation 
layer. If the chassis members are in contact with any salt 
deposits from roads this should immediately be washed off 
with a high pressure washer. Salt attracts moisture allowing 
the surfaces to remain wet, this prevents curing and also 
allows formation of wet storage stain.
It is recommended that the chassis/ components are washed 
off, using a pressure washer on an annual basis (especially 
after winter usage), to avoid undesirable build up of salt and 
dirt deposits. 
The galvanised chassis should not be painted or subjected to any 
other protective treatment. 
Should the galvanising become superficially damaged exposing 
the steel core, this should be cleaned and treated with a Cold 
Galvanising Spray obtainable from vehicle accessory outlets. 
Damage to chassis members through impact etc, MUST NOT 
be straightened or welded. Damaged chassis members MUST 
be replaced.
AL-KO CARAVAN CHASSIS  
						

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DRILLING OR WELDING OF 
PARTS OR ACCESSORIES
The chassis is designed and built to precise tolerances and 
must not be drilled or welded (except in accordance with 
certain AL-KO Accessory Operating Instructions). Failure to 
comply will invalidate all warranties.
INDEPENDENT SUSPENSION
The AL-KO rubber suspension is designed and developed 
to suit all types of road conditions and is maintenance free. 
Three rubber elements are contained within a hexagonal axle 
tube. These provide suspension and have inherent damping 
characteristics. (Only the hubs and wheel brakes require  
attention - see axle section).
LOADINGS ON COUPLING HEADS, OVERRUN 
ASSEMBLIES AND AXLES
The permitted ‘nose’ weights of the coupling head/stabiliser, 
overrun assembly and drawbars, must never exceed the lowest 
value stamped on the assemblies.  
The maximum axle loading is that stamped on the plate located 
in the centre of the axle, facing rearwards. The plate will be 
one of the three shown below - Figs 1, 1a and 2, depending on 
date and location of manufacture. The line marked ‘Capacity’ 
(on German plates ‘Achlast’) is the maximum permitted axle 
loading and must not be exceeded.
Where the Caravan Manufacturer states a maximum loading 
weight, then this is the maximum permitted load. This figure 
must not exceed the maximum axle load.
AL-KO CARAVAN CHASSIS
Fig 1 Axle Identification PlateFig 1a  New Axle Identification PlateFig 2 Axle Identification Plate (German)
AL-KO
    TYPE
     LE
         CAPACITY           kg
                25km/h
AL-KO
TYP 
A
ACHLAST
MOD.
EA           kg
TA            kg  
						

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LOADING
Loads to be carried in the caravan should be placed directly 
over, or as close as possible to the axles, otherwise the 
handling will be impaired. 
Maximum gross weight, as advised by the caravan 
manufacturer, must not be exceeded without approval 
from AL-KO. 
Maximum loading is defined as the difference between 
ex-works weight and the permitted total weight. 
Attention should be paid to the legal regulations 
regarding the permitted pressure exerted by the towbar 
on the towed unit.
AL-KO CARAVAN CHASSIS
High skid risk together with poor braking effect.
Optimum road holding together with maximum braking effect. 
Exceptionally heavy loads should be packed directly over the axle.
Steering and braking ability reduced. Increased loading on the rear 
axle and chassis of the tow vehicle. 
Fig 3 Load Too Far Forward
Fig 4 Load Too Far Back
Fig 5 Load Over Axle
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SAFETY PRECAUTIONS
No welding is permitted on AL-KO Axles. 
It is important that the wheel and hub/brake drum are 
compatible. This means that the PCD, wheelbolts and inset 
must all be compatible with both the hub/brake drum and 
the wheel rim. Particular attention must be paid to the 
recommended torque figures for the wheelbolts (page 16).
The axle type details shown on axle type plates must not be 
obscured or made illegible by application of any additional 
surface finish.
OPERATING INSTRUCTIONS
Service Brake
When the towing vehicle is braking or travelling down hill, 
the overrun device shaft is pushed in (dependent on the 
magnitude of the thrust on the shaft) and presses on the 
overrun lever. This acts on the Bowden cables and expander 
mechanism, which in turn expands the brake shoes applying 
the wheel brakes.
Reversing
When the towing vehicle is reversing, the overrun device shaft 
is pushing in, applying the brakes via the overrun lever, brake 
rod system, Bowden cables and the expander mechanism. The 
backwards rotation of the brake drum causes the secondary brake 
shoe to collapse cancelling out the braking effect, allowing the 
trailer to move backwards. At the same time the transmission lever 
swings back and compensates for the entire travel.
Hand Brake
With the Euro Hand Brake, pull the lever until upright. The caravan 
is then braked.
IMPORTANT NOTE
Please note that with the handbrake fully applied, the caravan/
trailer is able to move backwards by 25 cm until the spring 
cylinder/gas spring takes effect. 
AXLE TYPES  
						

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MAINTENANCE AND CLEANING
Maintenance of Euro-Plus/Euro- Compact and Euro-Delta.
The above semi-trailing axles come fitted with maintenance 
free wheel bearings (greased and sealed for life) and no 
adjustment is necessary.
NOTE
The hub bearing is not protected against water ingress. 
Check wheel brake linings for wear every 10,000 kilometres 
or every 12 months via the inspection hole (Fig 6/Item 1).
Adjust if necessary. Where continuous travel in hilly regions 
or high mileage is experienced, earlier inspection and 
adjustment may be necessary.
AXLE TYPES
Fig 6 Checking wheel brake linings for wear via inspection holes 
NOTE
The flanged hub-nut, located under the dust cap, used to keep 
the brake drum in situ, is a ONE-SHOT NUT (ie. must only be 
used once). If removed it must be replaced with a NEW flanged 
nut - torqued to 290 ± 10 Nm (214 ± 7.5 lbs/ft). A small amount 
of special mineral grease, available from AL-KO must be applied 
to stub axle thread prior to fitting the new flanged nut. After fitting 
excess grease must be removed with white spirit.
The rear hexagon cap head bolt MUST NOT BE DISTURBED 
under any circumstances. Interference with this nut will result in 
immediate tyre wear and damage to the braking system and WILL 
INVALIDATE ALL WARRANTIES. Should the rear nut accidentally 
be disturbed then the complete axle must be returned to AL-KO for 
resetting of the toe-in and camber. 
No attempt should be made to remove the bearing. In the event 
of damage to the bearing or drum, only the drum complete with 
bearing and circlip will be available as a spare. No grease is used 
in the hub other than the mineral grease on the stub axle. No 
grease should be placed in the DUST cap. This is not a grease cap 
as used in all previous hubs
1  
						

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‘STANDARD AXLE’ MAINTENANCE 
(TAPER ROLLER BEARINGS)
After 1500 km or 6 months
Have the axial play of the hub bearing checked and adjusted 
if necessary. 
After 10,000 km or 12 months
Check quantity and quality of grease, renew if necessary. 
With boat trailers which are driven into fresh/salt water, the 
hub bearing should be regreased shortly after contact with 
the water (with the exception of waterproof hubs). Check the 
wear of the wheel brake linings every 10,000 km or every 
12 months through inspection hole (Fig 6) and adjust if 
necessary. Where continuous travel in hilly regions or high 
mileage is experienced, earlier inspection and adjustment 
may be necessary. 
STANDARD AXLE MAINTENANCE
(SEALED FOR LIFE BEARINGS)
AL-KO Wheel Hubs are fitted as standard with Sealed For 
Life bearings which are maintenance free.
SPARE PARTS
Spare parts are safety critical parts! For this reason when fitting 
spare parts in our products we recommend the use of original 
AL-KO parts or those parts that we have explicitly approved. The 
reliability, safety and suitability of parts designed especially for our\
 
products, has been determined using a special test procedure. In 
spite of constantly monitoring the market we are unable to assess 
or vouch for other products.
If repair work or servicing is required, AL-KO have a large network 
of AL-KO service stations throughout Europe.
To establish the correct spare parts required for your axle you 
should always quote the axle type (axle identification plate Figs 1/2) 
and Spare Part Identification no. (ETI No.), which will be stamped 
onto the wheel brake or identification plate (Fig 7). Please establish 
these numbers before contacting AL-KO or a Service Agent. 
AXLE TYPES  
						

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The AL-KO rubber suspension axle has been designed 
& developed to suit all types of road conditions and is 
maintenance free.
Three rubber elements are contained within an hexagonal 
axle tube. These provide suspension and have inherent 
damping characteristics.
Figs 8, 9 & 10 show the deformation of the rubber elements 
at the extremes of suspension movement.
The axle is designed to ride with the suspension drop arm at, 
or slightly below, the horizontal position.
For Trouble Shooting & Fault Finding see Table 1 on page 44.
Fig 8 Rebound or Free Position
Fig 7  Spare Part Identification Number
ETI No.
811...
Fig 10 Maximum Bump
Fig 9 Normal Laden Position
AXLE TYPES  
						

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AL-KO BRAKING SYSTEM ADJUSTMENT
1.  Ensure the towing shaft with coupling head is pulled 
FULLY FORWARD. (Fig 11).
2. Release the handbrake to the FULLY OFF position. If the 
handbrake will not go down the whole way because of 
the fairing or any other obstruction; then the fairing must 
be cut away and/or the obstruction removed to achieve 
this desired position. It will not be possible to set up the 
braking system properly when the handbrake is not in the 
FULLY OFF position. (Fig 11).
3. Jack up one side of the caravan, using the AL-KO Side 
Lift Jack System. (See Jack Operating Instructions).
4. Remove the inner plastic bung from the backplate to 
expose the ‘starwheel’ adjuster access. (Figs 11 & 12).
5. ALWAYS rotating the road wheel in the forward direction 
- NEVER backwards; adjust the starwheel with a suitable 
screwdriver, in the direction of the arrow embossed 
on the backplate until there is resistance in the wheel 
rotation. (Fig 12).
6. Slacken off the starwheel adjuster until the road wheel 
turns freely in the FORWARD direction. (Fig 12). 
7. Check the adjustment at the end of the brake cable where it 
is secured to the abutment (bracket), welded to the centre of 
the axle. When the inner cable is pulled out it should extend 
between 5 and 8 mm. (Fig 13a\b). (On tandem axles a double 
abutment (bracket) is fitted to the front axle ONLY).
8. Repeat for other wheel or wheels. 
9. On tandem axles the brake cables from the rear axle should 
pass over this axle and cross over each other before being 
connected to the abutment (bracket) on the front axle.  Where 
ATC is fitted to a tandem axle caravan, the brake cables 
SHOULD NOT be crossed over.
10. Ensure the balance bar (compensator) is being pulled evenly 
(Figs 11 & 13a\b). Excessive movement to this bar (double on 
tandem axles) would indicate possible incorrect adjustment 
(if appropriate, repeat step No. 7 - Fig 13a\b).
11. Check the brake rod support bracket, (fixed to the floor) IS 
supporting the brake rod evenly. The brake rod MUST ALWAYS 
run straight, NEVER bent or curved under any fittings. On 
tandem axles, using the double balance bar, a brake rod 
support tube (Part No. 228827) MUST ALWAYS be fitted on the 
end of the brake rod, passing through the centre aperture on 
the abutment.