so if you get 275/40/17s in the front, is it normal to have 315/35/17 in the rear? I'm just a tad confussed....I understand what the middle number means, but i'm having a tough time finding that 275/35/17 for the front to match with 315/35/17. Sorry if i'm confusing you guys, but i'm looking to buy some goodyear gs-43s and having trouble finding that spec in those tires? Do they not make it?
Yes, its completely normal to run 275/40/17 up front and 315/35/17 in back. Both sizes are the same diameter. If you found a 275/35/17, your speedo would be off. It would be reading quicker then what you are actually going. Plus adding miles to your car that you hav'nt traveled.
Try this site if you want to mess with sizes.
Tire size calculator