Community Forums

DLane · 10-20-2008, 06:48 PM

I have test driven several Ventana DP coaches with Cummins engines and Allison 6 speed transmissions. There is a touch pad control for selecting reverse, neutral and drive. On this control there are also two arrows, one point up and one pointing down. Does anyone know if these can be used to manually control what gear the transmission uses. I would think this would be helpful when climbing grades where you could downshift in anticipation of the need rather than waiting for the coach to slow down before downshifting on its own.

DLane · 10-20-2008, 06:48 PM

I have test driven several Ventana DP coaches with Cummins engines and Allison 6 speed transmissions. There is a touch pad control for selecting reverse, neutral and drive. On this control there are also two arrows, one point up and one pointing down. Does anyone know if these can be used to manually control what gear the transmission uses. I would think this would be helpful when climbing grades where you could downshift in anticipation of the need rather than waiting for the coach to slow down before downshifting on its own.

Spikester · 10-20-2008, 07:21 PM

The uncomplicated answer is yes, these arrows are used to control the top gear your transmission utilizes. There is also a mode button directly above the up arrow which controls the transmissions shift points (normal and economy modes).

If you have not owned, or driven a diesel before, there is a learning curve one must go through to understand how to get the most out of your engine and transmission, whether it be speed, performance and/or economy.

Spike

porscheracer · 10-20-2008, 08:37 PM

Diesel torque curves are different from gas motors, and the horsepower curve is much flatter. Oftentimes (especially if you take fan operation into consideration), higher RPM = less power at the wheels. Pre-shifting, before you really learn the rig, will usually gain you some noise and worse fuel economy - not much more.

Explore America · 10-23-2008, 09:55 AM

Welcome to the forums! Allison has a video on their website which may be of interest: Pushbutton Shift Selector Operation(9:00). They also have another specifically on motorhomes: Motorhome Training(18:54). You'll need a "REAL"(.rm) compatible player to view the videos, and they can be a somewhat slow download from Allison's website, but informative none the less!

rmmpe · 10-24-2008, 04:50 AM

It's also important that you know the trans will not downshift until the engine is at a speed low enough to safely handle the downshift.

I'd say the trans was "Idiot-proof" but every time I do, God invents a new Idiot.

Explore America · 10-24-2008, 07:52 AM

I'd also say that the Allison is designed to be "idiot-proof" as pointed out by one of the videos. It won't allow you to do something that could damage the tranny. Case in point, I was taking a test drive with a Monaco factory rep. in a new coach at a FMCA convention. When we were cruising at about 55 MPH, the Monaco rep. told me to hit the "reverse" on the Allison keypad. Hesitating for a moment, with beads of sweat literally beginning to form on my forehead, I slowly pushed the "R" on the keypad. Sure enough, the Allison simply downshifted one gear. It knew that I actually didn't want, or otherwise, shouldn't reverse the coach at that moment. I wouldn't try this on a test drive without asking the dealer who is riding along. Many are not aware of this, and you just might end up giving them a heart attack!