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How to Understand Tyre Sizes from the Markings on the Sidewall

Model: (Various brands) Various
Part: Tires

If you want to know the sizes of the tyres fitted on your vehicle, in addition to checking the possible variants indicated in the registration document, which tell you what other types of tyres you can fit as alternatives to those currently mounted, check the sizes by reading the code stamped as follows: 255 is the width of the tread, expressed in mm. 50 is the aspect ratio. It is a percentage of 255 mm, so the sidewall is 127.5 mm (a lower number corresponds to a sportier tyre); R stands for "radial construction", which is the standard for 99% of tyres on the market: 20 is the diameter of the rim expressed in inches, and it must match exactly the rim of the vehicle.

Posted on 17 April 2026 by ScegliAuto

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How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

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