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akadeadeye · 09-08-2014, 12:18 PM

I have yet to use manual shifting on our Allison 3000 and ascending and descending mountains has worked out OK. But, I feel that I should know how and when to manually downshift to both increase RPMs on the ascent (to keep overheating to a minimum) and on the descent to keep speed down. I routinely use the engine brake on low setting on the descent but I wonder if I should also be downshifting. We are headed to the Rocky's later this week.

What do you do?

Don

jacwjames · 09-08-2014, 12:57 PM

On my 2002 Monaco Windsor I will use the exhaust brake whenever going down grades to save on my brakes. It provides for better control also. I will even use it when coming onto an off ramp or in city when coming to a stop light.

When I hit the button the transmission display shows 2 & usually 4, the gear it is in. If needed I will also use my brakes by providing short pulses of brake. Doing this I can usually maintain a safe speed.

I assume you have a high and low system on your 2009, if so I would not hesitate to use both on steep hills.

We drove up the Canadian Rockies on our way to Alaska and then back across from California to TN in 2009. The most "exciting drive" was when ascended and descended Bear Tooth Pass in Montana. Didn't have a problem but my wife's hands were tightly gripped to her armrest as she cursed me under her breath.

Practice as much as possible prior to entering the mountains. I don't even have to look for the button anymore, I can easily reach over and hit it knowing exactly where it is. This comes in handy for hard stops on the interstate.

Good Luck

**TonyDi** · 09-08-2014, 01:08 PM

In heavy climbing I try to keep RPMs between 1800-2000, that is where I make most power. If it drops I downshift. In descending I also keep the tranny in whatever gear I used to climb the grade. I engage the engine/exhaust brake before I start down.

Lots of luck and Happy Trails!!!

Cat320 · 09-08-2014, 06:14 PM

We crossed the CO Rockies last summer. I put it in D, turned on the engine brake and let it do it's thing. The engine temp went up seven degrees.

Gordon Dewald · 09-08-2014, 06:31 PM

Quote:

Originally Posted by akadeadeye

I have yet to use manual shifting on our Allison 3000 and ascending and descending mountains has worked out OK. But, I feel that I should know how and when to manually downshift to both increase RPMs on the ascent (to keep overheating to a minimum) and on the descent to keep speed down. I routinely use the engine brake on low setting on the descent but I wonder if I should also be downshifting. We are headed to the Rocky's later this week.

What do you do?

Don

I have observed on our coach the engine brake does the gear selection for you. When the throttle is fully closed the gear selector shows 2 and what the current gear is. It will autmatically shift down when the engine criteria is met. When descending a grade there would be no additional value in downshifting unless it were to limit the top gear that would be available when the footfeed is touched.

Uphill I have not had any issues as the transmission will shift down at the proper shift point to maximize the engine torque. Having the gear selection in econo mode will let the engine lug down farther than in regular mode. When climbing hills I shift out of econo mode if heating is an issue.