Good Morning, I am replacing the tires on my 2010 "I". It still has what I believe to be the OEM tires on it (Yokohama). After reading through the message boards and F8L's excellent tire guide, I am choosing the Bridgestone Ecopias. I notice when I am browsing the tire on TireRack.com, there are two different Ecopias listed with what is seemingly the only difference being the load index (89 vs. 91). What exactly does this mean and does it matter which one I choose? Thank you for the help!
Tire code - Wikipedia, the free encyclopedia 87 = 1,200 pounds each 89 = 1,300 pounds each 91 = 1,360 pounds each So with 91 your car could be 240 pounds heavier fully loaded than with 89. Toyota specifies both 87 and 89 for your car in different sizes http://www.toyota.com/t3Portal/document/om/OM47668U/pdf/sec_06-01.pdf (page 10 of the PDF, page 565 of the paper manual) Car and Driver weighed an empty 2010 at 3180 pounds with the fronts more heavily loaded than the rears LF 949 RF 978 LR 644 RR 609 http://media.caranddriver.com/ez/original/application/c4df488aab8502ae1efd564bc913ca03.pdf As you add passengers and cargo, more of the load will go to the rear tires.