Calpine
Southern CA
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Joined: 04/19/2008
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RayChez wrote: I am at Idyllwild right now at over 7K elevation pulling a 4400lb toad and the coach has performed flawlessly. Maybe so, but you ain't home yet.
Write again after you come off the mountain. 
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pfunk
Shelby Township, MI
Senior Member
Joined: 08/12/2008
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Diggin wrote:I drove some pretty gnarly mountains this week, and kept in mind all of the things I have always read here about mountain driving. I have done a bit of mountain driving, but wanted to work on using my service brakes as little as possible. Ended up using them too much again.
Way too many times I found my momentum building, RPMs increasing to the point of an upshift, then a few jabs of the brakes to slow things down again. I did some 8 and 10% hills in 2nd gear @25mph, and I had to jab the brakes more than I wanted. The 6 percenters were more challenging, because it seems that gearing and the exhaust brake should keep things more under control, but I would still have to work the brakes quite a bit.
I am running just over 36k combined weight on a 33k GVW chassis with a 330 Cummins. I slow way down on the summits, use the exhaust brake immediately, and watch my gearing closely. Just seems that the physics aren't working with me, or I'm not working with them. Sure makes me want to look into the PRXB upgrade.
My moral/advice: being aware of everything that is given here for advice should be thought about while descending. Keeps you constantly aware of what you are doing, and what your machine is doing. One needs to pay as much attention on interstate declines as on 2-lane-10%-cliff-on-one-side-downhills.
--kevin This is DW's scariest thing to look forward too. Worst thing I took her through was a seasonal road on Maui in a jeep, the next week, a road inspecter died from a rock fall. I havent been out west in about 18 years and that was in a car,, have the roads improved at all I remember dads ol cutlass wouldnt make it some of the inclines
2000 Holiday Rambler Endeavor
300 Cat 6spd Ally
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chuckster11
Idaho
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Joined: 04/30/2004
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Much of my driving involves grades, the temperature gauge is my guide. I keep downshifting to keep the rpms about 2 to 22 hundred. I tried to power over hills, letting the transmission choose the right gear and the unit would overheat.
Now I slow down going up hill and let that engine pull and stay cool.
I have no jake brake or exhaust brake so I use the transmission--somewhere between 3 and 4 depending on the speed.
I suspect each unit is pretty individual, some do better than others both up hill and down. The key is how hot your unit gets and how well comfortable you are on the downgrades.
I don't get in a hurry either way. Usually plenty of pull outs on grades to let you and your unit cool down.
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SIX PENCE
Sioux Falls, SD, USA
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Joined: 09/29/2002
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5-1/2 years, 75,000 miles, 49 states, every province and Mexico and I set it on economy and cruise control at 63 mph (my best mpg speed) and let it do it's thing. Use the engine brake as needed. Can count the number of times I have manually down shifted on one hand.
Have never overheated engine, brakes or tranny.
Capt. Bob & Pat (Alaska,Mexico, lower 48 & all of Canada)
Guard Dog, Curly the Cairn & Toby the Lahsa
Dutch Star DP 4097 2003
2005 Sport Trac
Datastorm Motosat (Locator #1974)(Internet & TV
"A moving target is harder to hit."
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SCHARLEY
Atlanta, GA
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Joined: 02/20/2005
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Looks like most of the replies are regarding descending, and most are recommending just letting the trans do it’s ting going up.
I would pretty much agree with what I see regarding the descent, I have a little different take on a accent.
I never want my accelerator on the floor waiting for my engine to be lugged down to the point that the trans downshifts. The reason is that in this condition you have no capability to increase speed because your engine is always operating at a saturation level. I always want reserve power. I never try to run up a hill as fast as I can because you’re running half out of control since you have no ability to accelerate if you needed to.
My recommendation is to down shift one gear at a time until you reach a point that you can maintain a constant speed climbing without having your accelerator pressed to the floor. Then when you approach the big rig you still have power to move over one lane and accelerate past without being stuck behind till the top because you had little or no power in reserve to make the pass efficiently. This practice will give you a true sense of being in complete control and will also eliminate most over-heating issues.
SCHARLEY
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