Tyre size advice

[Robdye]

Could I check that all is well with the tyre sizes on my 2020 C200 Estate -
Front = 225/45 R 18 Avon ZV7
Rear = 245/40 R 18 Continental Eco
Is this correct - do my tyre pressures remain the same?

 

[Bigdrew]

Hi Rob as to your tyre pressure it should tell you on the fuel flap

 

[Bobby Dazzler]

Hi Rob as to your tyre pressure it should tell you on the fuel flap

As suggested by @Bigdrew just use the tyre pressure printed on the inside of your fuel filler flap.

 

[Robdye]

Yea, will do of course, but it’s the mixed tyre aspect sizes I was more concerned with.

 

[Bobby Dazzler]

Yea, will do of course, but it’s the mixed tyre aspect sizes I was more concerned with.

Aspect ratio is a percentage of the tyre’s width: width (mm) multiplied by the aspect ratio is the sidewall height (mm).

Cars with a staggered set up - with wider tyres at the rear - must have a lower aspect ratio at the rear to achieve a similar sidewall height compared to the front.

Mercedes recommend a specific tyre pressure for front and rear, but this is due to the weight rather than the tyre size.

For road use tyre size makes very little difference to tyre pressure, unless you change the load index (best avoided).

 

[Robdye]

Great Bobby, so the differing tyre aspects here equalise the height and serve to handle the estate weight loads, Is this set-up is recommended by MB?

 

[Bobby Dazzler]

Great Bobby, so the differing tyre aspects here equalise the height and serve to handle the estate weight loads, Is this set-up is recommended by MB?

Those sizes sound about right. What does it say in your manual?

 

[Robdye]

Eh, nought!
Plenty of technical detail and safety coverall. I’ll visit my local tyre expert and get advice.
Otherwise fab car and enjoying trade up from A class

 

[OneForTheRoad]

Tyre sizes and pressures are all found on the fuel flap.