Mismatched tyre width
 

Can you use 235/40/18 on the rear and 225/40/18 on the front?

Bug eye, MY01

Running tyres of different sizes on a 4 wheel drive car really isn't the best idea.

Putting bigger tyres with a larger rolling radius on the back won't do the diff any good at all.

Try 215 40 18's all round

to be honest i would say not to due to the scooby's suffering mostly from under-steer rather than over-steer, mmmiddy says not to due to the diff, but to be honest its only a overall difference of 8mm in the circumference which is the equivelent of having new tyres on the rear and tyres with 4mm of wear on the front,can i ask why you want to put wider on the rear??as if its because your driving style would improve from this then i would say do it,it shouldn't be a problem,if its because you can get the odd sizes cheaper i would say don't do it.

Just curious thats all, noet special.

RWD drivers often fatten up the back.

Same ride height, IE 2**/40/** "40"

I thought a chance in ride height was the no no? not the width.

the '40' in the size is the 'aspect ratio' i.e,40% of 225mm = 90mm,so the sidewall is 90mm,40% of 235mm = 94mm,so the sidewall is 94mm.most rear wheel drive cars are set up to have the different sizes front and back,but as your car is not set up to this it will affect the overall handling which is not advised unless you understand what the changes will do,i.e understeer/oversteer/responsiveness.