Abstract: In a control system for a power shuttle transmission, the transmission comprises a first clutch pack engagement of which drives a transmission output in a first direction, and a second clutch pack engagement of which drives the transmission output in a second direction, and means to engage and disengage the first and/or second clutch pack, the control system comprising control means to initiate and complete engagement and/or disengagement cycles of the first and/or second clutch pack, and wherein the control system comprises adjustment means for actuation by an operator of the transmission to adjust the said engagement/disengagement cycle.

Abstract: A transmission casing for a tractor, eg on agricultural tractor, having a three point linkage for lifting implements, incorporates reinforcing bars (22) running the length of the casing to the top and on each side. Turnbuckles (26) allow the bars (22) to be placed in tension, thereby placing in compression the upper parts of the castings (1, 2, 3) making up the body of the transmission casing. In this way, the load bearing capacity of the casing the and thus of the tractor may be increased.