Allison Trans Econo Mode Button?

[Lucchese1]

On my last few trips I have been hitting the econo mode button on the trans shifter to better my milage but I honestly cant see any difference. I know from the video that it changes the shift points. I think the only time it would matter is in traffic conditions since on the hwy very little shifting is done. Has any one else had better results or ideas!

[Gary CA]

Ben: I have used the MODE in heavy slow moving traffic, also on the open road. I'll keep it to slow moving traffic because the shift points come up quicker for surges in traffic.

[smlranger]

I used econo mode on my most recent trip of about 750 miles...primarily rolling hills and flat terrain. There was a small improvement in mpg when compared to a previous trip over same terrain. However, I recently had a valve adjustment so not sure if that made improvements.

[John_Canfield]

I read somewhere (maybe on rv.net) a long, extremely detailed dissertation about the normal vs. 'economy' mode. Try a search over there. At a rally last year, the Allison people said to leave it in economy mode which is what we do most of the time.

[kenbt]

My understanding of the econo mode is when it is on it changes the shift points ( lower engine rpm)when on the highway after you are up to crusing speed to save gas. But when driving around town or in heavy traffic you would want it off so that the engine does less lugging as you try to get up to speed. You could almost compare it to using an overdrive in some transmissions except it does not give you another gear it just changes shift points so the engine doesn't rev as high before shifting

[Navy Flier]

The best use of the econo mode is in rolling terrain. Econo lowers the shift point. How much it is lowered is neither simple nor linear. Having a lower shift point in rolling terrain will keep you at a lower rpm (better mpg) for a longer period of time. You may not see much of a change in the short run but even 5% will add up over the miles.

[MrTransistor]

Hi All,
I have not been able to obtain any specific data on the difference in shift pattern between the two modes. Approaching 40,000 miles, I have not been able to detect ˜any' difference in the shift patterns between normal and economy. Unless we just got one that has both modes set the same. I haven't taken it to an
Allison dealer to have a diagnostic run. Has any one been able to pry this information out of Allison? I've gotten no response from them on a couple of enquires. If you have any info, would you post it for all to see?

[ajbjrvers]

TO; Lucchese1;

Always use the ECONO mode along with cruise control whenever. Using tem in unison, each computer, engine and tranny, tells it's component when to shift and how much fuel is needed. As yet, we mortals, can't think as fast or efficienly as computers.

As I said my ECONO light is always on. Getting almost 10 mpg, with 400 hp ISL and Cummins states it will get better after 25-30,000 miles.

Hope this works for you. AJBJRVERS

[jtharley]

While having my tranny serviced in Florida at a Detroit-Allison service center the tech took the time to show me how to read the "codes" that may come up on the trans. During that time I asked him about the economy mode and he said the only time he would recommend using it would be city driving with a lot of stop and go. Even then, the fuel savings is minimal unless you are a trucker going 100k miles a year.

He also said that I will notice a great improvement in fuel economy once the enginer has more than 20,000 miles.

[kenbt]

I found the factory information on how the transmission works. Go to page 19 of the below listed site. The entire site is good reading though



http://www.freightlinerchassisowners...sis_082004.pdf

[MrTransistor]

Hi kenbt,
I saw that document when it first came out. I know what they say I just don't know the ˜why fors'. As I said, I'm unable to find any specific data on how my (or your) transmission is programmed and again, I have tested both modes over many miles at several set speeds while observing the transmission shift points, manifold pressures, RPM, and fuel consumption using the CAT PocketTech and a Palm 515 and can detect no difference in any of the parameters or MPG.

It may be that on my coach, the transmission did not get the ˜economy mode' programming and both modes are set the same by default to the Allison standard programming. I guess the only way to know for sure is to have the program read out and printed at an Allison dealer.

[Fred Cooper]

I can feel the difference between economy and normal mode. The most dramatic illustration on my coach is during a full throttle merge into freeway traffic. The engine will go to a higher rpm before shifting to the higher gear in normal mode and I can get up to freeway speed much quicker in normal mode. After getting up to speed, I run in economy mode most of the time. If you can't detect a difference in full throttle acceleration, then maybe your mode switch is not programmed the same as my coach...Fred

[CHIPPYSGT]

I agree with Fred. I can tell the difference in the two modes, especially when merging. Also, in economy, which I generally leave it in when on the open road, the trans downshifts so smoothly going up a hill that I can't feel it; I only read it on the screen, though the rpm does go up a bit.

On my last trip to Charleston, SC I tested going slower. My mileage went up almost 1 mpg staying around 62-63 mph.

Doug

[bdpreece]

Econo mode effects shifting points, so be careful how you use it.
I am not sure if I really want this known or not but since we are still in one piece I will post it even though I feel like an idiot.
About 3 weeks ago we started out on our first trip in ages on a Friday evening. All was going well as we traveled down the interstate and I had the Econo mode on. It was after dark and we were in some hills coming up on a semi, I moved out to pass, pulled along side the semi and tried to accelerate. Since the transmission did not shift down I reached over to turn off the Econo mode but in the dark I hit the reverse button instead. Error lights started going off and naturally we were dropping back. Not realizing what I had done I was checking the errors and started to drift to the right into the semi. DW starts screaming and I missed him by a hair. Not sure I will try the Econo mode again for awhile. Did get to try the washer on the shorts though.