Is it a GM vehicle ? If so, tire dealers are supposed to match the TPC number specified for your vehicle. The Tire Performance Criterion specification number system identifys size, cornering stiffnesses, wet and dry traction, tread depth, mileage, noise, speed rating, rolling resistance, load capacity, revs/mile, mounting tear resistance, bruise strength and a few other factors. It's done to cover the legal implications of 'tire intermix': when people put baloney skins on their cars and trucks, have a crash, and then blame the vehicle manufacturer. Don't laugh, there are some really horrible tires out there and an outright menace to the owner/operator AND to those that get crashed into. I worked on developing this system because of the tragic woes some people got into because they were sold lousy tires. In fact, most vehicles are now detuned from Best in Class performance because of the aftermarket tire mess.
If a tire deal offers you some black thing with a really absurd name and model, stay away is the best advice you can give. Now go find some Adventurer Mud Booger Eaters in two sizes under your OEM tires (white letters make then even more dangerous) and put them on if you want to get rid of family members. Just loan them your vehicle.
