I've tried this twice with the factory, and they just won't do it! They say no custom orders! But on my '05, I was successful with the parts manager, at a cost of $1000, installed. That was from 18's to 18's. On this new one, the '06, the parts guy wanted too much, but I was able to make a trade with another '06 4.4i that the dealer had in inventory. The swap was even up for the wheels, (again 18's for 18's), but I paid for remounting and balancing tires. The wheels I got were on on '06 4.4 they were using as a demo, and the tires had about 2000 mi. on 'em.

Honestly, if I was the new car sales manager, I would have said "no", but I've made several friends at the store, including my salesman (he went to bat for me with the mgr), and this IS the 3d car I've bought from them.

To get an idea of potential cost, look up the retail cost of both types of wheels you're looking at, then figure the difference. On top of that, you must figure the cost to the parts dept. for inventorying the wheels you are trading in. That's where the "rub" is. If the wheels you want to turn in are not popular, or the parts guy thinks he will jhave trouble selling them, or just doesn't want to inventory them for a while, he'll add another couple of hundred.

BTW, on average, the dlr cost is ABOUT half the published retail price. Given all the factors, you may be better off buying the wheels you want outright from a dealer that advertises 25% off on parts, or persuading your parts guy to sell them to you at that price, then selling your 17's privately. Also, look at the wheels section on this site for used wheels, or others who are selling "dealer offs".

Good luck.

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Sageriders
2011 328, Water [blue], Saddle
2006 X5 4.4i, Sterling Grey/Truffle, Premium, Sport, Cold, Rear, Adj. Ride Ht.
2005 X5 3.0, Sterling Grey/Black, Sport(Totalled!)
2002 330i, Grey-Green Met/Truffle Br. [Sold]