My car blew a tyre a few months back but tbo it pulled the left before that.
I have recently changed the wheels to 18's and it is still pulling. The wheels being rebalanced (3 times!). Tyre pressure is steady and at the recommended pressure (33psi all round).
is tracking and wheel alignment the same thing or should i get the tracking looked at 1st and if that doesn't work then try 4 wheel alignment???
Ok, balancing has nothing to do with the steering pulling one way or the other. An unbalanced wheel would manifest itself as vibration through the steering (or even the seat/pedals if it was bad enough!).
Tracking refers specifically to the relationship between the front wheels, and how they point compared to one another. When the steering wheel is dead straight, most cars will have a partcular setting that they work best on. Toe out, where the tyres point very slightly outwards from each other, or toe in where they point very slightly together. Having them one way or the other will
help with turn in to a corner, stability in a corner and straight line, etc. Its all a compromise.
Alignment is sometimes the same thing, but usaually refers to all four wheels and their relationship to each other, also taking into account camber (and castor for those that measure it).
Tracking can be spot on, but the steering still pull one way or the other - my brother-in-laws Focus is doing this at the moment. He has 4 new matched tyres, correctly inflated, yet it still pulls strongly to the left on a flat piece of road. I think that he has bent a track control arm (which is part of the steering), or something fairly major to make it do this, but everytime its checked the wheels are all pointing exactly where they should be.
You putting bigger wheels on shouldn't make a big difference, except to tramlining, where the wheels want to follow the camber and ruts in the road. A bit like on the motorway where lorries make grooves in lane one, wider tyres will wander about in those grooves more than skinnier tyres. But as your car was doing it before you changed, I'd say its still something mechanical bent. Might be time to take it to an independant garage, explain what you've had checked and get them to make sure there are no damaged steering components underneath that you can't see.