Yup, now I see the evap cabinet and the refrigerant hoses. The tractor does not have full air brakes so they are either AirPack or no assist. By the time I was driving medium duty GM trucks from the early '70's, they were full air.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
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