Yes it is OK to use BMW's 4.4i's 19" wheels on your 3.0i. If you don't want to use BMW's OEM X5 19" wheels, then you can check out www.tirerack.com to see other options. Don't forget, you need to get the correct size tires.

If you get the 4.4i 19" wheels, you'll need 255/50-19 for front tires and 285/45-19 for the rear tires.

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