Now confirmed on several cars and by multiple sources, we have discovered that fitting custom wheels gives your 4 wheels/tyres of the same width. So in the case of cars that have wider rear tyres on stock rims, you lose rear grip and the whole balance of the car is ruined. This is an announcement of fact, not a debate. If you choose not to believe it for whatever bizarre reason, please keep it to yourself. The thread is here to be informative so I'd rather keep pointless debate out of it if you don't mind. See here: This is definitely an example of a cut corner in production and one I hope gets un-cut pretty soon. I realise its only a cosmetic sacrifice to leave the wheels stock on most cars but what's the point in being to 'upgrade' your wheels if it makes the car undriveable when you do.