General Motors has once again killed off the Impala SS for the 2010 model year. Starting soon, the Impala line will be available in base LS, mid-range LT and LTZ as a top-of-the-line. The loss also marks the end of the line for GM’s 5.3L V8 engine in the Impala, making the 3.9L LGD pushrod 60-degree V6 the most powerful available. Sorry bubble guys – there’s always motor swaps.