They will fit a 540, but the eights of the M5 and 540 are not the same so where you might get an equivalent drop in the back, the front will be higher as the weight of the M5 in front is heavier than the weight of a 540. The shocks have been valved for the weight of an M5.
'98 (04/98) 540i/6 Biarritz Blue / Sand Beige
Options: 17" Style 32 Staggered / Sport Seats / Xenons / Sport Suspension / 6 Speed / Cold weather Pkg
Mods: M5 Grill, CDV, AE Xenons, Rogue Engineering Octane Short Shifter w/ WSR, Rogue Engineering Performance Transmission Mounts, Royal Purple Synchromax Transmission Fluid, Gruppe M Filter Ram Charger
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