Depends on how much city driving you are going to do. the lower the aspect ration, the more your chances of blowing a tire due to a pothole or something. However, I would recommend the following:

19" rear: 275/35/19
19" front: 245/40/19
18" rear: 275/40/18
18" front: 245/45/18
17" rear: 275/45/17
17" front: 245/50/17
I really wouldn't push wider then these sizes, only because you would end up increasing the overall diameter and the weight increases with it, and whatever performance benefits you seek to gain really won't be achieved.

My advice. Try something like 18x8.5 up front, and 19x9.5 in the rear. I think it looks more aggresive then a 19" all around combo. MY neighbor just got an S500 the other day and his son bought 245/50/17 up front an 275/35/19 in the rear. Loooked intimidating indeed. Cheaper too (wheels and tires.) He Had Dunlop SP SPort 9000 in 275/35/19 in the rear, and Bridgestone RE730 in 255/50/17 up front.

Good Luck.

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Chirag (Charlie) Patel

- 99 Mercedes-Benz ML 430 V8 w/custom TV, Video, UHF, speaker system
- 93 190E 2.6 (4-sale) w/ an amp, equalizer, and CD-changer, integrated w. stock stereo for integrated cellular phone speaker system
- had a 93 190E m103 3.2, 5-speed trans,
- had a 88 300E 2.6
- had a 84 300TD w/275k+ miles
- 2002 S500/S600 - Maybe in a little more then a year