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2017 Mountain Mode - Some Observations

1410 Views 12 Replies 11 Participants Last post by  zeldar
2018 Volt LT 97,000 miles.

Just FYI:

I am on a cross country trip through the rockies, much of it off interstates. This is my first time mountain driving in a Volt though I am an experienced mountain driver. I started in Wisconsin. Here are a few things I observed.

I drove up a 6% incline at 70mph for 2.5 miles in Normal Mode and the battery indicated miles dropped from 37 to 16 miles in that distance. Those indicated battery miles ticked down remarkably quickly. I was wondering how hot the electric motors must have gotten drawing all that power.

I drove up another 6% incline of 3 miles in Hold Mode (16 battery miles left). Nearing the top the engine seemed like it was screaming at a very high rpm. The coolant temp was 217 degrees at the top. The car made it with no apparent reduction in performance, but I think I was at the edge of what that car is capable of. I understand physics pretty well and that engine had to be working pretty hard to lift all that weight at that speed. The battery charges nicely downhill. During the subsequent descent the battery mileage increased to 29 miles, but I don't know how far it was.

Those were the only 2 notable up slopes on this trip so far (Santa Fe to Phoenix), but the next mountain driving leg will be up towards Flagstaff then Moab UT. I will use Mountain Mode for the remainder of the trip in mountainess areas. I am be curious to see how well it works. I am also curious to see what the battery charge level (miles left indicated) will be on the "other side" if I start mountain mode with a near full battery of about 40 miles indicated. Will it return to 40 after each descent?

Downhill driving is a breeze in Low. I'm don't think I engaged the physical brakes at all. I'm pretty sure all of the downhill speed control was done via regen. But I don't know for sure.

Interesting trip. 9 days left of 15. After Moab, it's Rock Springs WY then Denver. Another learning experience.
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I have made many trips through mountain ranges (I live in Colorado) and I would recommend using hold mode while climbing in elevation. When you get to the top, switch to normal mode and let the car regen on the way down, leaving cruise control set and transmission in normal drive, not L. On a trip from my home to Las Vegas, NV, even though I used hold mode instead of mountain mode, some EV range was depleted, but easily recovered on the downhill runs. I simply kept the car in hold mode until the car was using 5kwh or less, then I’d switch to normal mode, and cycled that way the whole trip. Mountain mode in Gen 2 is not as effective as it was in Gen 1. Gen 2 saves roughly 20%, but isn’t as efficient at keeping up the 20% level. Gen 1 saved 50% and was far more effective at keeping the 50% stored for mountain driving. Anyway, I plugged in at my hotel in Vegas, and had 85 miles of EV range in the morning when I left to head for California. I was only able to get 58 miles of EV driving from the 85 projected miles, but I was also driving 80 mph for parts of the EV trip.
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