Q: I need to downsize wheels from 20" to 18". Is that recommended? My tires are 255/30 R20. What new tire size should I get?

asked by on December 29, 2017

I need to downsize wheels from 20" to 18". Is that recommended? My tires are 255/30 R20. What new tire size should I get if I downsize to 18 inch wheels?

My car has 45000 miles.
My car has an automatic transmission.

Hi Sriram. Thanks for sending in your question today. The 20" wheels on your BMW are likely plus (2) from OEM. Most 2013 BMW 328i’s come with standard with all four P225/45ZR17. Some BMW’s increase the OEM to 18" wheels, but decrease the aspect ratio to a 40-series tire. Here is what I always recommend to customers. Look on the inside of your driver door. There will be a sticker that indicates the original equipment tire size along with the recommended tire pressure. Purchase wheels and tires that fit these dimensions, then have the front end suspension aligned.

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