The introduction of an automated transmission signals both Kenworth’s and Peterbilt’s transition to its first built in-house gearbox for the T680 Advantage and Model 579 Epiq, respectively.
That transition, at least from my perspective on the Texas highway, should be as smooth as the transmission’s shifting. Sales of AMTs have soared the past three years among the two brands and AMTs have been spec’d in almost 60 percent of Model 579 orders this year. That’s up from 55 percent in 2016, which was up from 40 percent in 2015.
I took the new gear gearbox – outfitted in a Peterbilt Model 579 EPIQ and matched to a 455hp MX-13 engine – for a 120-plus mile spin around Decatur, Texas earlier this month.
The fruits of a three-and-a-half-year development program with Eaton, the Paccar automated transmission was made available for order in late August with an expected mid-October build date, and will be manufactured in Eaton’s San Luis Potosi, Mexico plant.
The 12-speed transmission – rated at 1,850 lb. ft. of torque and 110,000 GCVW and featuring standard eight-bolt PTO capability – isn’t a manual design with automated components. It is purpose-built as an automated transmission, which is why you won’t hear Paccar Powertrain engineers refer to it as an AMT.
The absence of an oil cooler, its lightweight aluminum construction and a lube system that only needs 16 pints of oil shaves about 200 pounds off the weight of a Fuller Advantage transmission and makes Paccar’s entry the lightest automated unit on the market.
