The 4.6is was available in 4 colors (black, imola red, estoril blue, and titanium silver). It featured 20 inch wheels, wider rims that were fitted over larger brakes than the 4.4. It also had rear fender flares along with different front and rear bumpers. The engine was based on an Alpina design. It had a beefier torque convertor. The 4.6 did have a continuous seam-welded chassis. The 4.4 HP was 290, the 4.6 has 340HP. 0-60 time for 4.4 was 7.5, the 4.6is is 6.2.The diffs ratio is 3.91. Supposedly it was not labeled an M because it was so different than M cars of the past (not a manual trans and was not rear drive)

As a diehard enthusiast, IMO, the differences are significant.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas