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Discussion Starter #1
I'm in the middle of changing all 4 tyres on the motor (I've just got the front ones on, and awaiting delivery of the back pair).

However after some checking, I've noticed the backs are currently the wrong size. They are meant to be 275/35 R20. BUT they've currently got 275/40 R20. (BTW, the fronts are 245/40 R20, which are correct as per the manual)

Do you know what impact this is having on the car. I do a fair bit of mileage, so would be good to know! Also, the correct size seems to be less common and loads more expensive!

Visually, the backs don't look overly larger or anything.

Thanks :thumbsup
 

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the main difference is that your speedo is reading slighty wrong at 70 mph your car is actually doing 73 mph no biggy but your wheel diameter is bigger as is the wall height of your tyre this may slightly affect handling , its not a major difference its about 4 % bigger than the old tyre and the recommended max difference is 3 % if it was me id put the correct size on it but its up to you :)
 

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I myself wouldnt worry too much as its just the rear is bigger by 3.3% shouldnt do anything wrong... "Could upset a few senors" but as you have had nothing go wrong with the car for having them on there for less than year or more...
 

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Discussion Starter #5
Cheers for the replies. I'm a little less worried about keeping them on for a bit.

Plus I'm pretty sure these slightly larger tyres are loads cheaper!

Anyhow, I'll get it sorted when I come to change them.

Cheers.
 
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