Allison 1000 Overdrive On/Off Switch

[troth]

I have a switch that is labeled "Overdrive" on the left side of my dash. The gearshift lever LCD readout says P-R-N-D-3-2-1. The OD switch is supposed to lock out 5th gear, and will allow me to manually switch to 4th or "D".... -But I'm not sure my OD switch is working. My questions are "how and when to use it":

a.) If I'm on cruise control, running down a flat highway at say 62 mph and flip the OD switch off, should it kick me out of 5th gear overdrive and put the tranny into 4th once I hit the switch?

b.) If my OD switch is "on", and I'm on cruise control at 62 mph in 5th gear (overdrive is in use), when I approach an uphill grade, the coach will drop from 62 mph to say 59 mph, and then the tranny automatically drops to 4th gear... Now, if it's in 4th gear and I turn my OD switch "off", will the tranny remain in 4th gear until I flip the switch back on?

[troth]

I have a switch that is labeled "Overdrive" on the left side of my dash. The gearshift lever LCD readout says P-R-N-D-3-2-1. The OD switch is supposed to lock out 5th gear, and will allow me to manually switch to 4th or "D".... -But I'm not sure my OD switch is working. My questions are "how and when to use it":

a.) If I'm on cruise control, running down a flat highway at say 62 mph and flip the OD switch off, should it kick me out of 5th gear overdrive and put the tranny into 4th once I hit the switch?

b.) If my OD switch is "on", and I'm on cruise control at 62 mph in 5th gear (overdrive is in use), when I approach an uphill grade, the coach will drop from 62 mph to say 59 mph, and then the tranny automatically drops to 4th gear... Now, if it's in 4th gear and I turn my OD switch "off", will the tranny remain in 4th gear until I flip the switch back on?

[rogueii]

If you are driving in OverDrive and flip the Overdrive switch off, You will drop to Fourth gear.
If the Trans. has already dropped to Fourth gear, it will stay there , if you turn off the OD switch--Unless the hill gets steeper, requiring 3rd gear. The Allison is a very High tech Trans and mine has been very reliable.

You should have a light in the switch, that lets you know it is ON.
I leave mine on, unless I am descending steep Mtns. I turn it off and drop to 3rd or second gear, if necessary, before I gain too much downward motion. This will help save you brakes. I traveled from FL to Washington, down to SanDiego, Las Vegas, CO,back through PA and down to FL last year. We did Yellostone, The Tetons, Glacier. I never had any problems.

[alvinc]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by troth:
a.) If I'm on cruise control, running down a flat highway at say 62 mph and flip the OD switch off, should it kick me out of 5th gear overdrive and put the tranny into 4th once I hit the switch? </div></BLOCKQUOTE>Yes<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by troth:
b.) If my OD switch is "on", and I'm on cruise control at 62 mph in 5th gear (overdrive is in use), when I approach an uphill grade, the coach will drop from 62 mph to say 59 mph, and then the tranny automatically drops to 4th gear... Now, if it's in 4th gear and I turn my OD switch "off", will the tranny remain in 4th gear until I flip the switch back on? </div></BLOCKQUOTE>Yes

D-3-2-1 corresponds to
(5,4)-3-2-1

The Overdrive switch allows you to disable the 5th (overdrive) gear. Tuning off the switch is the same as manually shifting the transmission to a lower gear. Of course you don't want to overspeed the engine.

[alvinc]

It is probably worth mentioning that there is another possible shift pattern, that actually makes the overdrive switch useless. How do I know? My tranny was programmed with the incorrect shift pattern. I had a little difficulty getting, Fleetwood and Allison to believe me. I took it to the Allison service center and they test drove it, and still didn't believe it; thought that was how it should be. They were kind enough to call the internal Allision help desk, and voila, they had heard of it. The service center downloaded and installed the correct firmware.

DETAILS:

Correct shift pattern with overdrive panel switch:
D -3-2-1 shifter corresponds to
(5,4)-3-2-1 gears

Alternate pattern if no overdrive panel switch is available:
D- 3 -2-1 shifter corresponds to
5-(4,3)-2-1 gears

Note that this allows the driver to shift to "3" to lock out overdrive without having a panel switch. I presume that this if for panel trucks and non-RV types of applications.

There are two ways to notice the difference. One is that there is shifting taking place when the gear shift is in 3rd. The second, and best, is on a slight downhill with shifter in D, overdrive on. When you turn off the overdrive, there should be a downshift (both will do this), then when you move the shifter to "3" there should be another downshift (keeping within RPM limits of course). If you cannot effect a downshift by going from "D" to "3" you may have the wrong transmission programming.

[troth]

Thanks for the answers guys... My switch is clearly not working because it simply does nothing under the two conditions I mention above.
Now to the next question: Is that Workhorse or Winnie warranty? (or Allison?)

I love my Allison too, and I want all it's features to work properly. By chance is there a little fuse for this OD switch?

[alvinc]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by troth:
Now to the next question: Is that Workhorse or Winnie warranty? (or Allison?) </div></BLOCKQUOTE>Based on my experience, if you call Winnie, they will refer you to Workhorse, if you call Workhorse, they will refer you to Allison. I am not sure who actually footed the bill for my work, though I doubt it went beyond Allison.

I went through the entire chain. Can't help you much there. I would push hard for a Allison service center visit (hopefully there is one nearby). Once at the service center, with a copy of this thread, use the info I provided. BTW: the firmware version I needed was Version "VW".<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by troth:
I love my Allison too, and I want all it's features to work properly. By chance is there a little fuse for this OD switch? </div></BLOCKQUOTE>I doubt it, it is just a open/close type of switch.

Good luck.

[abarkl]

I don't have an OD switch with my 1000. So what's the shift pattern and how do I control it?

[alvinc]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by abarkl:
I don't have an OD switch with my 1000. So what's the shift pattern and how do I control it? </div></BLOCKQUOTE>More than likely you have:

D- 3 -2-1 shifter corresponds to
5-(4,3)-2-1 gears

Of course yours could be mis-programmed and you go straight to 3rd gear from 5th. The negative to this is that you cannot hold in 4rd gear on a downhill. Hope you have a small RV because this will place more stress on the brakes. In essence the only holding hear you have is 2nd and below. This is exactly why I was concerned and pushed it through the chain.

I do not know if the switch can be added aftermarket. I am sure they would charge for the firmware change.

As an addendum, the Allison 1000 locks the torque converter after second gear. So if you really pay attention you will experience: 1-2-LU-3-4-5. In fact when there is a downshift it will release the shift down, releasing the lockup at the same time, establish the lower gear, then lock back up. Smoother shift this way. You should see approx 1000 rpm on each shift, 300-500 on the lockup.

On my Plymouth Van and Wrangler the lockup does not occur until after the highest gear.

[Blaster]

I have the over drive lock out switch which work's great, also have grade brake switch on lower right panel that make's big difference starting down hill. With grade brake it down shift's for you when you touch brake's.

[rvten]

abarkl are you sure you have an Allison 1000 trans. Have not heard of any without a lock out OD switch. Maybe you have the GM 4 spd trans that came on the P series chassis or on the W-16/18.

[abarkl]

Yes, I have the 1000 with Allison printed on the pan and the filter that I've installed. I have the W22 chassis.
I too wish I had the switch!

[alvinc]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by abarkl:
Yes, I have the 1000 with Allison printed on the pan and the filter that I've installed. I have the W22 chassis.
I too wish I had the switch! </div></BLOCKQUOTE>That's a bummer.

If I were you I would figure out which transmission programming I have and then price having the switch added. To do this shift manually throught the gears and observe the RPM changes. In first gear, there should be nothing, shift to 2nd and you should see two rpm changes. One for the shift to second and another when the torque converter locks up. The important gear to observe is the shift to 3rd, is there only one shift or are there two. Continue onward to "D", are there two shifts or just one.

Now the analysis: If there are two shifts in 3rd, then your shifter "D" is your overdrive control. In order to upgrade this you will need both a transmission re-program and the switch added.

If there is only one shift in 3rd, but two in "D", your transmission is programmed incorrectly since it does not have a OD lockout switch. There are a couple of ways to look at this;

a) WH or the coach builder got the order wrong. Good luck persuing them on a 2001 chassis.

b) Or, you don't need the transmission programming, just the switch. Seems like this would be cheaper, there might even be a un-terminated wire someplace waiting for a switch. Think positive.

In any case, determine which programming you have.

BTW: you should add your RV manufacturer (Fleetwood, etc), line (Pace Arrow, Southwind, etc), and model (35R, 32V, etc) to your signature.

[rvten]

On my 2001 Winn. Adventurer. Switch just has Overdrive on/off. Not lighted either. You must have the only Allison 1000 in a MH without the OD switch.