Originally Posted By: supton
I gave serious thought to RAV4 a while ago, and one of its allures was the "lock" button. Instead of waiting until the rear slips to engage the rear (or to deliver more than 10% torque, whatever) you could "command" it to "lock" the rear in at 50%. And above a certain speed (35mph?) it would revert back to its FWD bias.
Honda's VTM-4 is similar. Our MDX has that system, and it has a "VTM Lock" button on the dash. That locks the rear differential clutches so you actually have true 3-wheel drive. The rears are locked together (like a locker) and it's locked to the propeller shaft, which spins at transmission output speed. So it's impossible to get a front wheel to spin without the two rear wheels spinning at the same time.
It defaults back to "automatic" operation above 18 mph, but even its automatic operation is somewhat proactive, and it works very well. I certainly favor their VTM-4 system over the Real Time AWD. That said, we own one of each and both get the job done.
I gave serious thought to RAV4 a while ago, and one of its allures was the "lock" button. Instead of waiting until the rear slips to engage the rear (or to deliver more than 10% torque, whatever) you could "command" it to "lock" the rear in at 50%. And above a certain speed (35mph?) it would revert back to its FWD bias.
Honda's VTM-4 is similar. Our MDX has that system, and it has a "VTM Lock" button on the dash. That locks the rear differential clutches so you actually have true 3-wheel drive. The rears are locked together (like a locker) and it's locked to the propeller shaft, which spins at transmission output speed. So it's impossible to get a front wheel to spin without the two rear wheels spinning at the same time.
It defaults back to "automatic" operation above 18 mph, but even its automatic operation is somewhat proactive, and it works very well. I certainly favor their VTM-4 system over the Real Time AWD. That said, we own one of each and both get the job done.