Australia-based David Boulton runs a small trucking company with two trucks, running the east coast of Australia pulling mostly singles and sometimes doubles. He operates a 1998 Kenworth T601 and a 2005 Kenworth T604. The T601 is a 10th anniversary model, boasting a 550-hp Detroit 60 Series with an 18-speed Eaton. It's rated at 50 tons and pulls mostly singles. The T604 is rated at 90 tons and pulls mostly doubles, powered by a 550-hp C15 Cat with an 18-speed Eaton. Boulton said the T604 "has been one of the best trucks I've owned." Both rigs run between Brisbane, Sydney and Melbourne.
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