my 2001 bugeye wrx wagon has 40mm tires all round but id like to go back to 45 or 50,the rears need changing soon. Would it be ok to put bigger on back? Ive done it before years ago on other vehicles but never on a 4 wheel drive! Thanks. Reason i want to go bigger is because i live in london and lots of speed bumps and potholes around.

 

No, tyres need to be matched all around.

Fine on a 2wd car not on a 4x4/AWD.

 

Quite simply you'll f*ck your centre diff due to the different rolling radius of the tyres!

 

There's also no such thing as 40mm tyres, 40 is a percentage of the width You need the same rolling radius front and rear or it'll wind up the centre diff and cause damage.

 

Ok. Thanks.