How do you drive in the Mountains ??

Check the door for the maximum weight to load your car. I suggest not to exceed that limit on a long drive. I believe it is 800 Lbs. so it looks like your OK. In long down hill drive say going down a huge mountain use the shifter to slow down the car. If you ride the brakes you may overheat them and than the brakes fade or don't work. Take it slow the car will do Great on a long trip. Up the mountain use Power mode. Take a few breaks and try and walk around A little to get the blood circulation going and avoid blood clots for older passengers the back seat may be uncomfortable for long drives for some people. Keep in mind there temperament. Sirius subscription at be good to pass the time. Audio Books. Prius Chat is on A podcast albeit it is older recordings. A iPad and data plan may help pass some time.

 

Just a FYI the breaks have 3 systems, so if primary fails secondary kicks in and if primary and secondary fails a Third system kicks in. In total break failure pump the breaks. The brakes are among the best in production cars in backup systems.

 

I live in the mountain and a three of my families Prii do great. "B" Mode is your friend

 

The car does great in the mountains if someone who knows what they are doing is driving.

In the Prius, Power/ECO modes don't actually do anything to increase or decrease the power. They just remap the throttle. In the real mountains with lots of people, you are going to be pedal to the metal up the hills. DO NOT let off the accelerator, once you do you are screwed and will never make your speed up again. This is usually the first fatal flaw people make driving up the passes in any vehicle. They let up the gas for an instant, the car gets out of high rev power and into low rev cruise even though still going uphill, then the speed drops like a rock, and when you punch it, the car struggles to find gearing to get power again. I've seen every kind of vehicle stuck in the 50 mile per hour range crawling up the hill because they did something stupid. The Prius is capable of ascending and maintaining 80+ miles per hour on the steepest grades of I-70. But not if you don't floor it and keep it there.

As for handling as in cornering, on an interstate in the mountains it is fine. It doesn't "corner like it is on rails", but it will do.

Forget about gas mileage, but through the mountains expect periods of infinite gas mileage read out at 99.9mpg and then equal periods of 8mpg to 20mpg. Yes single digit 8. On average, you should stay in the 40's.

I find it best to keep it in D until the battery is nearly charged and up to all but 1 green bar. Generally you don't want to drive in the green, but on the next climb you are going to need all the power you can get. Once it gets to 7 bars full, shift to B mode to slow down. Only use your brakes if absolutely necessary. It is extremely annoying on a mountain pass to be in a line with someone upfront riding their brakes. In the winter weather which lasts from August through May, all that braking could be on ice instead of just going through it. Treat the brake like it is a precious resource, and it is. In the Prius you are saved by having regen braking go to the battery and then you can take over engine braking instead of engine braking and friction brakes. Overheating the brake pads is a concern, but if you drive as suggested, it won't even be close to a worry.

And as you might have guessed, the battery will be going from empty 1 bar to full 8 bars every time you go up and then down a big hill. This is stressful to the battery and it will heat up. Make sure to NOT block the vent on the passenger rear seat. This will probably kick on at some point and start getting loud. This is to cool the battery off. Don't do like one person I know and cover it because it was noisy! It is noisy, but it is saving your battery.

 

the B is awesome for going down long hills/mountains.

more importantly, have fun and don't sweat the small stuff to save a few dollars.

 

Doesn't Power mode keep another bar of charge in the battery by default? So, driving in Power mode should help a bit every time you're about to approach a severe grade.

As an alternative, they can always keep right with the trucks and trailers.

 

Get a few caffeine drinks along the way to keep alert. If your tired pull over and rest. Try and not exceed 10 hours per day behind the wheel. Split driving responsibilities if possible and stay in a hotel overnight. Avoid Alcohol drinks. Eat 3 square meals. Avoid junk food if possible. Tell you credit card company about your trip so they approve your charges. Use navigation. Have fun. Don't get a speeding ticket which should be easy with a Prius.

Let us know how you make out.

 

A couple or three thoughts...

Applying partial brake pressure on a Prius doesn't result in brake pad to disk contact at first. So no heating of brake pads and rotors is taking place. You will feel braking, but its regenerative... you are making electricity... charging the battery for the next climb. You get very effective braking from regeneration. Your Prius calipers clamp down on the disk when stronger pedal force is applied. Slipping the dongle to "B" will also manage your speed on downhills, but don't think it makes as much battery juice in the process. You can use both brake pedal and "B" to manage speeds in the hills.

Anyone more technically minded on the Prius please correct me if my statements are flawed.

Mountain driving... If you want to save a little fuel on long climbs, switch off the cruise and let the speed back off a tad, 5 to 10 mph and then just keep it steady. Make up the time on the downhills.... but not too fast!

Check your tire pressure before you depart! Pack as lightly as you can... but most importantly, have a fun and safe road trip!

 

After the battery is full, any pressure of the brakes results in friction braking.

B mode simply uses some of the regenerated energy to spin the engine as an air pump wasting it again. This results in going slower and less energy recaptured into the battery pack.

 

Is energy tapped from battery when you do that? If so, how long does it last?

 

When you push the accelerator to the floorboard, yes the battery is being drawn upon. Depending on the health of the battery you can either pull 120A out or until it goes into voltage limiting mode around 180VDC. You can sustain this until the SOC drops to 1 bar (~40%) and then the Toyota algorithms go into protection mode and prevent battery usage as much as possible.

You don't need much power to sustain your movement and speed up the hill. The anemic ICE will do that job just fine. What it cannot do is accelerate you up the hill without battery help. So if you are constantly on and off or even just go to adjust the pedal, you will lose speed until you mash it again, and you won't be able to reclaim that speed until you crest the top.

In the Prius the problem is a lack of power because that is not what it is meant to do. The gearing eeks the maximum out that it can and will always be in the perfect gear to do so.

In conventional cars, the exact same thing happens but because the gearbox cannot cope with finding the right power point for the acceleration you demand. Only in very powerful cars can you drive like a dope and still make it up.

I've done the same mountain roads in various Honda Civics (one hybrid auto, one conventional manual 5sp), Lexus RX's, Subaru's (legacy/impreza/forester), Toyota's Rav4 and 4Runner and even an early 90's corolla.

The Civics also had similar power to the Prius, but because the gearbox sucks, it could not maintain speed up the hill no matter what. It would slow to 60-ish and peg there in the automatic whining and lurching. The manual if you put it into a lower gear it would make it, but would overrev with more speed. Shifting up would take all the power away and it would under-rev. So you were stuck with a high revving engine in a lower gear again around 60 miles per hour.

We have taken our RX300, RX350, RX400h, and RX450h over the same passes before over the years. With each model came slightly more power, but it made it up everytime at speed. If you dropped off the gas, it would take some time to catch back up, but it would make it. The 400h and the newest 450h however are just beasts, and with a similar drivetrain to the Prius, the things eat mountain passes like they don't exist. You get power and a good transmission.

One of the older Subaru's had the power to make it up, but pushing it at the higher in-spec rev's through the passes always over heated it. It was predictable even to which mile marker the temp gauge would reach critical on either side of the pass. So when we took that we would put the heater on full blast with maximum air flow and roll all the windows down. That bought just enough time and cooling to make it through the worst of it.

The Prius takes the mountains like a champ, but you can't be chinsy with the throttle.

 

My first hand experience is that Power mode is not necessary at any elevation below Pikes Peak, even ECO mode will do the job. But I have no experience at elevations above that.

Do learn how to use B mode on long steep descents, don't overheat the brakes.

 

We drive in the California Sierra Nevada mountains regularly and our Prii do fine, even on ice and snow. Drive sensibly and your Prius will do fine in the mountains and you will be rewarded by excellent mileage.

 

The road up to Pikes Peak is pretty tame, very touristy. It is high in elevation but nice and slow going. The back ski roads behind the peak is where the Prius gets put to the test, but it does just fine. I have a great view of Pikes Peak from my deck.

 

Is it better now that it is paved all the way up? It wasn't when I was there.

 

Drive it to ski a lot.

Just drive normal. Keep up speed with the rest of the traffic.

"B" braking is nice for downhill especially if single lane and line up develops. Keeps you off the brakes.

 

I haven't been up since it was paved. I went up when it was mostly dirt and no guard rails. But the grade is easy.

 

^^ But it is higher and steeper than anything OP and spouse should encounter on their trip.