Cruise Control Signal Generator

I had the same thing happen to our '92 U-280 (4 speed Allison, C8.3 L Cummins). James Triana told me you can figure out if it is the main cruise control unit (mine was a Bendix) or just the “signal generator”: Start the engine, keep the parking brake on, use the cruise control knob (stick, whatever you have) and increase the idle (as though you were “resuming” your speed). If the rpm's increase (as shown by the tach), then the problem is in the signal generator, not in the main control board. The signal generator screws into a “T” at the transmission port, along with the speedometer cable.

If it is the generator, it's “good news and bad news”. The good news is that if you can find one, it's a simple job to replace (about 5 minutes; Barry Beam helped me replace mine) and not very expensive; the bad news is that if yours is similar to my unit, they aren't made any longer (as of the summer of '09), according to FOT. I would hope that FOT has found another source by now – Don Hay