Miley Cyrus' New Car — Benz Over for $127k

Miley Cyrus and her new Mercedes BenzMiley Cyrus can go from 0-60 in 5.3 seconds … without a top on … and all it cost her was a cool $127,000 … has learned.

Cyrus dropped by a Mercedes Benz dealership in Encino, CA last week … and drove off the lot in a brand new white 2012 SL550 convertible.

Sources close to Miley tell us … the former Disney star paid for the entire thing up front … because she can.

The best part … Miley didn”t even turn in her old car … a bodyguard drove it back to her pad so she could joyride in her new toy.

The lesson — it”s good to be rich.