Within Cliffjumper burns the spark of a hero and a dedicated Autobot. On the outside he's a paranoid, trigger-happy jerk with serious impulse-control problems. Cliffjumper utterly hates the Decepticons. He also hates traitors. And anybody could be a traitor. Therefore, Cliffjumper hates everybody. It's unclear if he hates traitors more than he hates Decepticons, but it's at least a neck-and-neck thing.
He makes a habit of pulling ridiculously huge guns out of nowhere and attacking impulsively despite orders or sanity. Somehow, this gets him neither killed nor demoted.
Cliffjumper's special weapon is his glass gas, which embrittles metals on contact so that they shatter like glass. He is not immune to its effects, so its use requires careful consideration of wind direction. Actually, this may explain why he prefers the big guns. He doesn't seem like the calculating type.
His alt-mode is a Porsche 924 Turbo.