Allison V730

The Allison V730 is a three-speed automatic transmission used in several makes of transit bus including the RTS, Canadian-produced GM New Looks, and Grumman Flxibles. Later production buses in the GM and Flxible line had the Allison V731 transmission, which is essentially the same unit but controlled electronically, with a keypad replacing the familiar shifter-lever in the driver's compartment.

The Allison V730/V731 family transmissions also come in versions with a built-in retarder (the VR731), and a version allowing transit agencies and others to use right-turning Detroit Diesel family motors (variously the V731R or V731RH) instead of the standard left-turning units found in Flxibles, GM New Looks and RTS equipment.

Most installations of the V730/V731 have them coupled to the DDA 6V92TA two-stroke diesel, but Canadian GM 'New Look' production T6H-5307's had them mated to the then-standard 6V71N. Some Canadian production 1982 "New Look" models featured the 6V92 mated to the V730, such as Vancouver, B.C.'s 1982 T6H5307 "Hillclimber" buses, all of which have now been destroyed except for the one example belonging to the transit museum "TRAMS."

In 2000, the Toronto Transit Commission started to retrofit New Flyer's 1990 D40HF buses from the ZF ECOMAT 500 transmission due to failures. What they noticed is that due to the lack of the retarder which the Allison V730 does not have, the TTC should have retrofitted the transmissions with the Allison VR-731 which have these.

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