Robert Foxworth voices Ratchet, the team's medical officer. He transforms into a search and rescue 2004 Hummer H2. The writers had wanted to keep his original ambulance form, but the producers wanted something else. Hasbro did not mind if the character was either an ambulance or a fire apparatus.
For Dark of the Moon, Ratchet had some changes done to his vehicle mode, which was painted green and white.
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