It looks like you have 2 different style of seals?? The spring is there to keep the seal tight on the shaft especially when there is some movement like there is with the front axle shaft. If you put some heavy grease on the spring it will stay in place better when you install the new seal.

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1988 325is (purchased new) sold
2004 X5 3.0 2005 X3 2.5
2008 X5 3.0 (new to me)