What is highest speed to use engine Brake?

No speed limit on "B" mode. Engine RPM is controlled by the HSD. It won't let it over-rev.

 

It's been posted before that "B" mode should only be used for long downhill grades where the brakes are being used. It forces the ice to run thus wasting gas.

 

Any speed is okay, but why would you want to use it for that purpose? Press the brake pedal and recapture more of that energy.

Tom

 

I have used B mode at 85 or 90 MPH coming down long steep mountains with a full battery. The car will protect itself and will not go beyond the 5200 RPM red line. I have seen it up to about 4800 in B mode however.

 

It really is counter to everything my dad taught me about hills and slowing down from high speeds. Then again, from driving behind (and smelling) people who don't have regenerative braking, I don't think alot of people know that you can smoke your rotors by riding the brakes down the pass.

 

The Prius requires a little different technique. But as others have said there is nothing to be gained from using B unless the battery is full, or unless you know the road and are sure it will be full before you get down the hill.

With proper use of regeneration I think our friction brakes will last for a lot of miles.

 

Ive found if you use the cruise control when you are going down a long grade, it will use regenerative braking until the bars are full, and then it will automatically use engine braking.

 

Yes I've see that also, good feature I think. Probably means we don't really have to select B, we can do it with our foot.

 

I agree B for steep downhills, generally brakes are cheaper than CVTs!

 

Your Prius doesn't have a CVT in the mechanical sense, so you don't need to worry about that. While your assertion is flawed, your conclusion is correct.

Tom