Converted highway tractors do not last long. The lightweight single frame, light axles, and air suspension all conspire against it. Most highway trucks have 12,000lb front and 40,000lb rears, while tandem dumps need 16,000lb to 20,000lb front and 44,000 or 46,000lb rears. The rear suspension needs to be a walking beam type- either Hendrickson or Chalmers. The common 10 speed and 13 speed transmissions do not have low enough gears. A dump would need either a 8LL or 15 speed. Check the
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