Ive changed a few CV axles, and i always seem to have to pull the axle in snug, ive used OEM ones, cheap chinese ones, and mid grade ones. they all seem to need some sort of assistance to fit! (the only one that didnt was the original one, with the boots (and grease) changed!! even it needed to be snugged in the last 1/4 inch with an axle nut, Ive only ever experienced this with BMW!! ive checked the back of the hub and the new axles, and they all seem fine, just snug! so i made up some tools and not had any problems since!!

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2003 X5 3.0i (02/2003) sport package, Sapphire black metallic / Black Dakota Sport seats. compass mirror retrofit, trailer hitch retrofit, Prodigy P2 trailer brake controller installed, PDC retrofit, Lumbar support retrofit. heated rear seats retrofitted. Running boards retrofitted and subwoofer install in progress. 4.8is Brakes installed front and back. Bluetooth TCU installed, Rear Fog lights installed. Retrofitted reclining rear seat backs.