Truck tyres must always be in good condition and have sufficiently deep tread. Otherwise, you and your vehicle pose a danger to road traffic. The legislator does not show any leniency in this regard either. If you are caught with tyres whose tread does not comply with the regulations, you have to pay a fine of 60 euros and get one point added to your licence, while your employer has to pay 75 euros and also gets one point added to their licence.
As a driver, you must be able to change your tyres yourself, for example if you change from winter tyres to summer tyres in a truck or vice versa – or in the event of a puncture. Although you already learn this during your training, if you do not carry out the work steps for a long time, your memory fades. We will therefore explain the process again step by step.
Jack up vehicle with lifting platform or truck jack
First you have to jack up the truck – this is done either with a jack suitable for trucks or even better with a lifting platform. The basic requirement for this is that you have learned how to use the relevant equipment or that a qualified person is present to help you. It is particularly important that the truck is lifted properly and securely so that you can work on it safely.
How to remove the truck tyre
Now loosen the nuts of the wheel bolts. The best way to do this is to use a noise-reduced pneumatic screwdriver. In order to comply with occupational health and safety requirements and to protect your ears, you should also wear hearing protection. Once the wheel is loose, grab it from the outside with both hands and carefully pull it off. Ensure you follow good ergonomic procedures, otherwise the weight of the tyre can quickly lead to back pain.
Cleaning and deflating truck tyres
The rims may be covered with brake dust. This should only be removed during wet cleaning (ideally in a wheel washer). If you whirl it up during a dry cleaning, you may breathe it in – and this has dangerous health consequences. Now let the air out of the cleaned tyre. To do this, unscrew the valve core using a valve extractor.
Removing tyres on the truck tyre changer
The tyre changer allows you to easily remove and fit new tyres onto the rims. It is important that you place your bead breaker as close as possible to the rim flange without touching it directly. If the tyre is very tight, you can continue turning the wheel several times and loosen the beads by repeatedly using the bead breaker.
Now clamp the wheel on the tyre changer. For alloy wheels, use clamping jaws or guard rings to prevent damage to the centring. Make sure that air pressure sensors are present and replace the old valve with a new one. Then adjust the tyre fitting arm to the correct tyre size (here it may help to follow the manufacturer’s instructions). Undo the beads one by one until you can remove the tyre.
Check the truck wheel rims carefully
Slowly turn the wheel on the machine and check the rim carefully. Are there any dents, cracks or rusty spots? If necessary, consult experts and carry out minor repairs. It is important that the rim is in good condition for the upcoming journeys.
How to fit a new truck tyre
If the rim is all right, the next thing you do is to take a look at the registration document. You can use the information in it to check whether the rim and tyre sizes match. If you use a powder for balancing, add it according to the manufacturer’s instructions. The next step is to apply the lubricant recommended for the rims and tyres. First you have to brush the rim from rim flange to rim flange with the lubricant – Attention in case of sensors – take care so as not to get lubricant on them!
Also apply lubricant to the tyre from both sides up to the centring line inside and outside. Then place the tyre on the rim and use the mounting hook to pull the first bead over the first rim flange without using force. You should also apply lubricant to the mounting hook. Make sure that the mounting hook does not touch the rim! At the same time, it must not be positioned too far away from it, so that the tyre is not stretched too much. It may be necessary to readjust several times when fitting to avoid damaging the rim or tyres.
Once you have pulled the first bead over the rim flange and pushed it into the well base, reposition the mounting hook to bring the second bead over the rim flange as well. You should be particularly careful in the last third, as the tyre is under very high tension here. So proceed in small steps and add more lubricant if necessary. Take care that the bead does not curl up or buckle. Once the tyre is finally seated, carefully remove the mounting hook, if necessary with the aid of the mounting lever.
Take care when increasing the tyre pressure!
Damaged tyres or improper inflation with compressed air can lead to accidents in which the tyre bursts or is catapulted away. Special care must therefore be taken. Tyre fitting systems that are also inflating systems are ideal. These systems are safe and save time and money. In some European countries they are mandatory. This is not the case in Germany, but it is strongly recommended to use a tyre inflation cage. If not, you should maintain a distance of at least two and a half metres.
The tyres should only be inflated in stages. So that the tyre can ‘settle’, i.e. press airtight on the rims, you should increase the pressure according to the manufacturer’s instructions. For a car, only 3.5 bar is recommended, but for a truck a tyre pressure of up to 10 bar may be necessary. Ensure that the tyre sits evenly on the rims.
How to fit the new truck tyre
Check the finished tyre for cracks or other minor damage and make sure that it is regular in shape. Allow the lubricant to dry and clean the hub, bolts and nuts of the wheel during this time. Then you can take the finished wheel to the truck and first attach it loosely. First loosely fasten it with two opposing bolts before attaching all the others.
Centre the wheel using two wheel bolts. Then tighten all the others only halfway before you lower the truck. Then use a torque wrench and proceed in such a way that after tightening one bolt you first fasten the opposite one, then the one next to it together with the one opposite it and so on. Important! Do not use a wheel gun for this last tightening operation! Otherwise there is a risk that you will exceed the permissible tightening torque.
Adjust the inflation pressure
After fitting, you must adjust the tyre pressure to the prescribed level. This can be found in the application table of the tyre manufacturer. Even if you have only replaced one truck tyre, you should check and correct the pressure in all tyres.
Summary: Take care when changing truck tyres
If you want to change one or more truck tyres, you should proceed strictly according to the regulations. If you do not do this, you may experience problems either during the process or later while driving. You should have a trained specialist teach you how to handle the jack and the truck tyre changer. The most dangerous part of tyre changing is the inflating with compressed air, which can lead to serious accidents. Accordingly, you should only carry out this work using a tyre inflation cage, even if it is not prescribed in Germany. Once the finished wheel has been securely fitted to the truck, adjust all the tyres to the prescribed pressure.