Comment Re:Will this work with autos? (Score 2) 88
Auto gearboxes dont like being towed because they require fluid to be pumped around else gears start grinding pretty soon.
I think that's only true of automatic transmissions. (Manuals have the gears and shafts immersed in oil. Automatics require the oil to be pumped, to provide power for the logic and actuators to lubricate some shafts/beraings that require oil injection because they aren't immersed, and to circulate it through an external radiator and/or heat exchanger in the engine coolant radiator (which then also would like the engine to be running to run the water pump) to cool the fluid which gets heated by the moving parts.)
Older transmissions only have a pump on the front (engine side) shaft. So the transmission isn't cooled and lubed if the engine isn't running. This limits towing speed and duration (unless you disconnect the drive shaft or put the driven wheels on a dolly or raise them off the pavement.) That's why to companies usually haul auto-tranny cars on a platform. It also means you can't push-start the car, because it won't shift into gear without the fluid pressure from the pump.
Some modern automatic transmissions also have a rear pump (on the wheel-side shaft). This provides fluid pumping even with the engine stopped, which lets it be towed longer and faster (especially if the vehicle has a transmission oil cooling radiator), may allow it to be push-started, and lets it use engine braking without rising loss of braking (both engine drag and power brakes) and power steering if the engine stalls and stops turning. ("Tow-haul mode" in vehicles with the towing package.)
So this conversion looks like it would work on a manual or a rear-pump auto transmission, but would also need an extra electric tranny fluid pump on a front-pump-only automatic transmission.