Ditto on everything motordavid said. since you drive it so infrequently, you definitely need a trickle charger. BMW also offers (was $80) a charger that plugs into the lighter.

Personally, 5 yrs and it's gone. need it or not. I did see the Interstate battery truck deliver to my dealer. Go with after market & save $150 vs dealer costs

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Mark _______________________________
2001 X5 4.4i topaz blue/sand Sport, complete Dinan S2 , hitch, V1, tint, BSW Stage 1, Alpine INA-W910BT
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