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As the previous owner of a Gen II Prius, I had learned a couple intricacies of the hybrid and braking systems to maximize mileage and minimize mechanical brake wear. This knowledge came from "PriusChat" forum, my own experience and use of the ScanGauge.

1) In the Gen II Prius, I read that below 7 mph the mechanical brakes always engaged when braking, no matter what. It's not something that worried me too much since I understood that its affect on brake wear was negligible (hard braking at high speeds has much greater affect, think of KE=1/2 MV^2). Is there an equivalent speed for the Hybrid RAV4 where the mechanical brakes always engage?

2) In the Gen II Prius, there was an ampere limit to regenerative charging (I had a scangauge, programmed an X-Gauge for HV battery amps). It appeared to be about 93 amps +/- a couple depending on temperature. I have yet to discover an X-Gauge for HV battery amps on the RAV4, but the dashboard has a Hybrid System Indicator (a unitless pseudo-tachometer/energy charge-recharge meter). I'm wondering if when the needle pegs in the recharging direction, is that the recharging limit (i.e. harder braking will engage the mechanical brakes)? Or, is there even more recharge amperage capacity that is difficult to discern by looking at the gage? I'm assuming the RAV4 Hybrid has even more favorable recharging capacity due to the rear axle Motor Generator.

The reason knowledge of these two factors could be handy is in situations where you can see far ahead a slowing situation which allows yourself to control the braking effort throughout the slowdown to avoid engaging the mechanical brakes.
 

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The Rav4 system is identical to the Prius in all respects. There are minor differences due to having a different final drive ratio. And yes, it has 4-wheel regen braking, although I doubt it is able to charge any faster or "harder" than the 2wd systems. The limitations of charging are not related to the MGs, but due to the capacity of the inverter/converter and the physical cables in the system.
 

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If the engine is running whenever car is moving, effectively you have a mild hybrid. To maximize MPG, most recommend pulse and glide - meaning get up to speed quickly then let go of the gas and re-press to set it to run on battery.

As far as braking, long slow deceleration to maximize recharging/minimize brake use. Many mention their Prius brake checks show that the brakes have barely been used at all. Great news for probably never needing to replace the brake pad and using the brake fluid to its max time before needing to replace (due to moisture creeping in).
 

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Brake fluid usually needs to be replaced since it is hygroscopic (absorbs moisture), more than because of the amount of use. In a relatively high moisture situation in winter here (buckets of rain) fluid needs to be replaced about each two years. One can buy an inexpensive tester (Amazon, etc.) which warns when fluid contains too much H2O.
 
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Under normal conditions (battery not overheating - i.e below 41C, or battery not fully charged - i.e. below 80% SOC), the regeneration limit is 27.5 kW. For everything above that it will use the brakes.
 
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