My car has different tire sizes on the front and back wheels. Can the spare still be used for both the front and rear?

Yes, this is what is commonly referred to as staggered tire sizing. We have carefully designed the spare for vehicle models with staggered sizes so that it can be used on both front and back without issue.

Vehicles with staggered tire sizes front to back will typically maintain the same or close to the same overall rolling diameter on all four tires. Some models, however, have variances in tire diameter from front to back. Rest assured that even for these vehicles, the tire size used on the Modern Spare will be ideal for that model and for normal use.