dgpcolorado wrote: kikngas wrote:
Ah, so that's why I've not found the indication of power used by CC.
On the brake lights, I've done my share of engine braking down hills as well. But it's much easier to just tap the brakes enough to flip on the lights when your other use of the energy is to burn gas to slow down
In fact I would always pump the brakes both so they can cool a bit in between, and to catch the eye of those behind me more than once and get them thinking about the stoplight at the bottom of the hill or etc. ...which they oftentimes seem to do, but there's always that one that darts into the right turn lane and floors it to get to the stop sooner. Or better, use the right turn only lane to pass those turning left that have stopped the lane that goes straight or turns left. That makes a very safe environment for the oncoming that is trying to turn left and can't see the right turn lane coming straight for 'em.
When driving mountains in Colorado, using engine compression to control speed on downgrades is something of a safety issue, especially for heavy trucks. Since the engine is at idle fuel levels, the gas used is trivial. Even automatic transmissions should be using lower gears. Riding the brakes for many miles down a steep grade isn't a good practice. Since most mountain roads have a lot of curves, just going down at terminal velocity isn't usually an option, even if it was legal. Many downgrades here have emergency truck ramps for use by out-of-control trucks (but it would be a mighty scary ride until the truck came to one of those).
Same situation applies here, for instance on I-80 from west of Tahoe descending towards Sacramento. There are signs on the steepest grades (I forget the slopes, but there are sections at least 6%, but they might be 8 or 10%) which read
Let 'er drift
Let 'em cool
with runaway ramps spaced appropriately. The steepest slope I've seen signs on was Hwy 108 just east of Sonora Pass, which is either 25 or 26% and very narrow and windy (several hairpin curves), but that's much too narrow for trucks. Old Priest Grade on the way to/from Yosemite is one I routinely drive, and in the days of drum brakes it was not uncommon to see cars coming back from Yosemite at the bottom that had drifted out into fast moving cross traffic on Hwy 120 (despite using compression braking all the way down I barely stopped short of it a couple of times in my '65 Impala), and the people who lived at the bottom had a hose in their driveway for people to use to put out brake fires - it got plenty of use, and they also had a guest book for people to sign who'd used the hose.
I did have to show my friend how to use the lower gears in his automatic 4Runner when descending this and other steep downhills - apparently many people who've never driven anything other than an automatic are unaware that they can do this.
Sometimes people say "but it's so much cheaper to replace brake pads than a transmission" (this assumes that compression braking is hard on an engine, but it isn't as long as you keep the revs below the red line, using brief brake applications to do so and coasting in between). Some time after I'd gotten my license I raised that point with my dad the truck driver, as to why it made more financial sense to use the brakes. His reply was something along the lines of "If your transmission fails, you signal, pull over to the shoulder, call a tow truck and then repair or replace it. This may cost you a couple thousand. If your brakes fail, you may not be _around_ to have them repaired or replaced for less. How much is your life worth to you?"