Ford was stupid to stop the beloved Escape Hybrid

 

I understand the Escape Hybrid will be back in a couple of years.

The Rav4 Hybrid is interesting. Press reports say the Rav4 Hybrid will, at least at first, be sold only as an awd.

Rather than a driveshaft like the FEH used to power the back wheels, it will follow the Toyota hybrid suv approach of using a third electric motor for the back wheels. It remains to be seen if this unit is subject to overheating and disengaging in demanding circumstances.

One benefit of this arrangement is that regenerative braking can be done with both the front and rear wheels, unlike the awd FEH which only regenerates from the front wheels. So the braking done with the FEH's rear wheels is wasted like a normal car.

Given the rear wheel regeneration and technological advances since the FEH was designed, plus better streamlining, one would expect the Rav4 Hybrid to get better mileage than the FEH. Since the Rav4 Hybrid isn't on the road yet, we have only the published mileage numbers. Surprisingly, those numbers are a bit worse than the FEH gets in real-world reports.

 

Interesting knowledge...I read that for $500 more, the new RAV4 Hybrid also have an option to equip a technoligy that can stop the car right before a collision automatically...

 

The RAV4 hybrid is essentially a 'down-market' version of the Lexus NX300h that has been out a year already.
The NX300h AWD was rated at 32MPG combined, while the RAV4 is rated at 33MPG combined ( it's probably lighter).
The '17 Escapes will have auto idle stop/start and will probably have the same MPG as the old hybrids did
The Highlander/Lexus RX hybrids have never had a rear driveshaft, they've always used the separate dedicated rear motor (a few early models were sold as FWD)

 

So, Escape Hybrid 4WD with a rear driveshaft, for traction wise in winter snow, should be better than separated rear motor? Because driveshaft is a truck design...

 

EIt all depends on how it's set up. The Escape awd uses an electronic coupler in the rear axle. I understand it's subject to overheating in severe use and will disconnect in that event. I've never experienced it happening though. Its operation is controlled by a computer that monitors a variety of sensor. Presumably it also has a limit lower than taking 100% of engine power to the rear axle. It does not "torque vector" between the two rear wheels, while the traction control keeps from sending all the power to the wheel with the least traction.

A rear electric motor can be subject to overheating and disengaging depending on the amount and duration of force its designed for. It can be designed to torque vector, though I don't think this is used below luxury car levels.

So presumably a rear electric motor setup CAN be more capable than a rear driveshaft setup. One clear advantage of the Toyota design is that it allows regeneration of braking forces from the rear wheels, which the Escape design can't do. A rear electric motor would allow propulsion from just the rear wheels, which the Escape design also cannot do.

 

The rear electric motor on Toyota/Lexus may have some limitations in how much torque it can provide, as it was mainly designed to boost acceleration. On extended low traction surfaces when the HV battery is depleted, it may switch to primarily FWD operation and regen. An 4WD Escape Hybrid will always have AWD available (as long as it's not overheated!) irregardless of HV battery state.