Quick one this lads as my MOT has crept up on me. I need my front tyres replacing and many people have stuck 195/50/15's on my car instead of the stock 195/55/15 as the tyres are cheaper. I only need the front two done as the FWD has trashed them. So obviously if i get the front two replaced, they will be on 50 sidewall and the rear will be on 55. So the question: If the sidewall height on the front is different to the rear, will it fail the MOT? Answers ASAP as i need to get it booked! Preferably from those in the know. VOSA site simply states that the "tyre size/type and tread depth" are checked so isn't particulalry specific on requirements. Someone with the MOT guidelines would be bonza! I need some exhaust work done before the MOT too and as such am on a shoestring, otherwise I would just bite it and buy it. Thanks chaps. EDIT: Just found THIS site for anyone interested but wont be able to go through it until i get back from work - as a result your input is still very much appreciated.