You dropped $50k cash on an X5? I'm sure that's correct since you get it cost ~$60k and you have a loan for 3 years on $10k.
Even if you have a sh1te load of cash around, why didn't you invest it? Throwing $50k into a depreciating asset when you could have leased the vehicle, saved on payment, invested your $50k and the extra you save per month, you would have been able to get a return that far exceeds the decrease in interest from only having a $10k loan.
my $.02