Tyres W211 Sport 2007

[Palmersol]

Hey, could someone tell me.... I have a W211 sport with 265-35-R18 on the front and 245-40-R18 on the rear now I'm not sure why the front has 40's and the rear has 35's?? I suppose it something to do with the weight of the engine??..well I'm guessing!
would it make any odds to put 40's on the front and rear? I know it all comes down to the gear ratios but??? to be honest I don't have a monkies

 

[markjay]

I am assuming you meant to say that you have 245/40 R18 at the FRONT, and 265/35 R18 at the REAR?

If so, then the rear tyres are wider. This is known as 'staggered' wheels.

In theory Rear Wheel Drive cars with lots of power need wider tyres at the rear to avoid wheel spin when accelerating - but in reality the 'staggered' wheels is more for visual effect on cars with the 'Sport' trim (lowered suspension, spoilers, etc).

However, the wider tyres at the rear should still have roughly the same diameter as the narrower tyres at the front... for this reason the rear tyres have 'lower' profile, i.e. 35 at the rear instead of 40 at the front.

You will find that 35% of 265mm (92.75mm) is *roughly* the same at 40% of 245mm (98.00mm)....

 

[markjay]

If you fit 40's at the rear, the car will drive just fine.

However, chances are that the rear wheels (not the tyres, the actual alloy wheel) are wider than the front wheels, to accommodate for the wider tyre rubber.

So if replacing the rear tyres with 40's, then check first that the wheels are all the same width - this is measures in a unit called 'J', e.g. '8J' wheels are 8" wide, while '8½J' wheels are 8.5" wide.

If the rear wheels are wider than the front ones - then you will need to change not only the rear tyres, but also the rear alloy wheels themselves to narrower ones.

And last... a reminder that you should notify your insurer of any change to tyre or wheel size.

 

[streethawk]

If you fit 40's at the rear, the car will drive just fine.

However, chances are that the rear wheels (not the tyres, the actual alloy wheel) are wider than the front wheels, to accommodate for the wider tyre rubber.

So if replacing the rear tyres with 40's, then check first that the wheels are all the same width - this is measures in a unit called 'J', e.g. '8J' wheels are 8" wide, while '8½J' wheels are 8.5" wide.

If the rear wheels are wider than the front ones - then you will need to change not only the rear tyres, but also the rear alloy wheels themselves to narrower ones.

And last... a reminder that you should notify your insurer of any change to tyre or wheel size.

Rears are wider.

 

[Palmersol]

sorry for the delay as iv been away for a few days,
thanks for the info Markjay very informative just needed to make sure before I order a new set of boots, as you can imagine getting a full decent set isn't going to be cheap.
Top man thanks