Mountain driving challenges

[xrep]

We just drove over the Rockies and were faced with some real challenges. Going over some of the passes, our Pri ran out of juice and used the gasoline engine exclusively. It was almost like the clutch was slipping and in order to keep the engine from over-revving I had to feather the gas pedal. Going down the other side of these passes, the battery went from zero charge to fully charged in as little as 5 minutes. This seemed pretty quick to me. I was troubled at how hard it had to work to get over the mountains although it was during the mountain driving that we got our overall best mileage. Is that over-revving normal?

[cwerdna]

<div class='quotetop'>QUOTE(xrep @ Aug 2 2006, 10:21 AM) [snapback]296388[/snapback]</div>

We just drove over the Rockies and were faced with some real challenges. Going over some of the passes, our Pri ran out of juice and used the gasoline engine exclusively. It was almost like the clutch was slipping and in order to keep the engine from over-revving I had to feather the gas pedal. Going down the other side of these passes, the battery went from zero charge to fully charged in as little as 5 minutes. This seemed pretty quick to me. I was troubled at how hard it had to work to get over the mountains although it was during the mountain driving that we got our overall best mileage. Is that over-revving normal?
[/b]

I haven't driven over the Rockies but have gone up the mountains (Grapevine are) between the SF Bay Area and LA.

I wouldn't be concerned about "over-revving". You obviously discovered the battery capacity isn't very high and well, the Prius ICE is only 76 hp (not much for a 2890 lb car). I'm sure that there's a rev limiter and that it'd be virtually impossible to go over/into the redline RPM range.

[sl7vk]

<div class='quotetop'>QUOTE(cwerdna @ Aug 2 2006, 01:27 PM) [snapback]296398[/snapback]</div>

I haven't driven over the Rockies but have gone up the mountains (Grapevine are) between the SF Bay Area and LA.

I wouldn't be concerned about "over-revving". You obviously discovered the battery capacity isn't very high and well, the Prius ICE is only 76 hp (not much for a 2890 lb car). I'm sure that there's a rev limiter and that it'd be virtually impossible to go over/into the redline RPM range.
[/b]

I drive over parleys regularly.... It's a rather steep hike going for 4500 feet to 7700 feet in less then 20 miles. The car does struggle a bit, but I've found that just leaving it in cruise and letting the car do all the work works just fine. The car hardly ever only uses the ICE, but most of the time the ICE is powering the electric motor as well. I get down to the Magenta bars pretty quickly on this route, but it takes me a hell of lot more then 5 minutes to recharge the battery going down the other side of the pass.

[powphilprius]

I've had my prius since last June, went on quite a few ski trips to the rockies last winter since there was no snow in NM. I found out the same thing, the juice runs out and your left with ICE power. I just let it rev like hell and got to all my ski areas no problem, just a little slower. Put on about 10K miles on ski trips. Haven't had any issues. I would like to be able to add a big battery to somehow switch in for the climbs. Maybe someday...

[dipper]

Resist the Torque Luke.....

I went up the Rockies on I80 last year with the Prius. It is very steep. The torque on the Prius is so good that you want to jack rabbit up the incline. I say use the momentum as much as possible and start slowing down a little at a time. That way, you would not have to use all the battery juice.

At one point, I was driving at 40 mph up the mountain and no battery was used... I had two bars left and did not want to use it all up... Of course, about a minute later, I found myself on the peak already...

[richard schumacher]

That hill-climbing roar may sound alarming because the engine is normally so quiet, but it's perfectly normal and harmless. The computer(s) would have to fail before the engine could "over-rev". There's no need to annoy traffic behind you by slowing down to 45 MPH or whatever. Enjoy the full sensation of blast-furnace power impelling you ever-greater heights.

(OK, so they were having a sale on hyphens.)

[Rancid13]

I haven't had any difficulty with driving the Prius up and down and all around various mountain passes throughout Southern CA (Cahuenga, Tejon, Cajon, Sepulveda ) and parts of Northern CA (the passes btwn San Jose and Santa Cruz). It does sound sometimes like you're taxing the engine, but I don't believe any damage is being done. Just like when you accellerate to get up to speed getting on the freeway, the engine revs loudly, but I don't think the computer will allow over revving, like richard stated in the post above.

Perhaps the most memorable climb was the Sherwin Grade (just north of Bishop on hwy 395 en route to Mammoth Lakes, CA). It's a ~20-mile ~3000-4000 foot climb and the Prius handled it just fine. Got my worst gas mileage ever (low 30's) and down to 2 purple battery bars, but the car never lost power or made me feel like it was having the least bit of trouble. With my previous car (a Saturn), I had a heck of a time keeping up speed going up that grade, the RPMs would get near the red zone on the tacho and that kept me going much slower than I wanted to. No issue at all with the Prius.

I'll get the pleasure of travelling up the Sherwin Grade again towards the end of the month, when we go to Mammoth (and possibly a bit of Yosemite) for several days. I have no worries, and am 100% sure that the Prius will be just fine with all the summertime mountain driving as I've only had experience with wintertime driving thus far with it.

[galaxee]

since this question has been answered pretty thoroughly i thought i'd just add that there is no clutch.

[tmorrowus]

The biggest problem with hill climbing in the Prius is simply that people are afraid to let the car do it's thing. It does rev high sometimes, but you don't have to worry about that. The car's computers won't let you take it into the "danger zone", so you can be secure in knowing that there's no harm in flooring the accelerator up a hill.

What I really like about the Prius on hills is that it's always in the perfect gear. On regular cars you're usually in too high of a gear, making the car slow to accelerate, or too low of a gear, making it jumpy. Or you're in the process of shifting, during which you have no power at all. The ICE in the Prius is underpowered relative to other vehicles, but it makes up for that by always being in the right gear.

[Rangerdavid]

Since I live in the mountains, and regularly transverse a 1500 to 1700 foot altitude change just going to and from work, and often up to about 6000 feet on some of our "hills", the reving of the engine you describe is probably normal, just as is the read out of 10-12 MGP on the climbs. Its just that your last car, like my former Xterra probably got very bad gas mileage, I just didnt have a real time read out to see it.

I'm sorry to hear that you had this degree of difficulty on the trip. I have experienced no problem whatsoever living here, but it does require me to drive a bit differently (like you describe feathering the pedal, and the battery does charge rapidly if you're on a 2-3 mile descent) than I would otherwise drive in the flat lands. As I was told when I moved here as a Park Ranger years ago, everything's different here... and it is, even the driving methods.

good luck!!!