gtspeed100

I want to go wide as possible with no problems.

Thanks!

MustangFirstCar

275s, 285s are all good.

275/45/18 and 285/40/18 have about the same total diameter so you won't even have to re-tune the speedo, plus they will fit fine on 9.5 rims very well.

Jas5

On my wheels, and stock GT500, front is 18x9 with 255/45/18 and rear is 18x10 with285/40/18....

I imagine you could do anywhere in between... I'd probably go 275/45 so there isnt so much bulge

Nuke

I believe the max on an 18 x 9.5 is 285 and the min is 255, which is what the GT500's were equiped with, rear and front respectively. I'm currently running 275's all around on 9.5 width rim and wish I had done 255's front/285's rear.

ExpatMedic

I have 285's on my 18x9.5 and 295's on my 20x10s, both look great, neither have really any bulge (unless you're going for the import stretched look)