340 Tyre pressure may prescribe a certain type of tyre for your vehicle. In addition, the use of specific tyre types may be advisable for certain regions and areas of operation. A tyre dealer, a quali- fied specialist workshop or any Mercedes- Benz Service Centre will be able to provide further information. Observe the recommended tyre pressures and check the tyre pressure of all the tyres including the spare wheel: R every day before starting a journey R when the load changes R prior to long journey Replacing tyres R for changed operating conditions, e.g. off- road driving If necessary, correct the tyre pressure.
If replacing the standard tyres of your vehicle, use only the tyre and wheel sizes approved for your vehicle type. A tyre dealer or a qualified specialist workshop will be able to provide further information. After changing the tyres, always carry the operating permit for the new tyre and wheel size as well as the manufacturer's certifica- tion indicating that the wheel/tyres are per- missible for use on the vehicle. The speed- ometer will also require adjustment. Observe the relevant legal requirements for each country. Any Mercedes-Benz Service Centre can provide information on obtaining a man- ufacturer's certificate.
G WARNING The tyre temperature and pressure increase when the vehicle is in motion. Reducing the pressure of warm tyres leads to a tyre pres- sure that is too low when the tyres have cooled. If the tyre pressure is too low, it may cause the tyre to burst, especially when the load or speed increases. There is a risk of an accident. You should never reduce the pressure of warm tyres. Observe the specified tyre pres- sure. Wheels and tyres ! An increase/decrease of 10 † in air tem- perature increases/reduces tyre pressure by approximately 0.2 bar. Remember this pressure change - particularly in winter - when checking tyre pressures, e.g. in a garage. Example:
The room temperature in the garage is approximately 20 †. The outside temperature is approximately 0 †. Adjust the tyre pressure so it is approx- imately 0.4 bar higher than indicated in the tyre pressure table. When you leave the garage, the tyre pres- sure drops by approximately 0.4 bar. Retreaded tyres Mercedes-Benz recommends that you only use tyres and wheels which have been tested and approved by Mercedes-Benz specifically for your vehicle. Tyre pressure Important safety notes G WARNING Tyres with insufficient or excessive tyre pres- sure harbour the following hazards: R the tyres may burst, especially as the load and vehicle speed increase.
R the tyres may wear excessively or unevenly which can severely impair tyre traction. R the handling as well as steering and braking characteristics may be severely affected. There is a risk of an accident.