What is the "Economy" setting?

[OldHiker]

Exactly what is this, like an overedrive? Does it really work?

[OldHiker]

Exactly what is this, like an overedrive? Does it really work?

[Nathan Focht]

It is supposed to improve fuel economy. However, I was told that it would only work on absolute flat terrain and that I should never use it.

[soricobob]

No, it is not like overdrive-which used to have an extra top end gear, which allowed the engine to travel at high speeds and lower revs. This economy just changed to gears in a more economical way, but if you are towing, it won't matter much to your economy.

[rebelsbeach]

Here is a link to the operation manual....Pages 16 and 17 describe the "mode" button.



Allison Tranny Manual (pdf)

[paz]

The only "Economy" setting on my motorhome is with the ignition switch in the "OFF" position.

[OldHiker]

[QUOTE]Originally posted by rebelsbeach:
Here is a link to the operation manual....Pages 16 and 17 describe the "mode" button.
QUOTE]

That's why I was asking for a clarification. I can't find anything about it.

[dieselclacker]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by paz:
The only "Economy" setting on my motorhome is with the ignition switch in the "OFF" position. </div></BLOCKQUOTE>

Good one Paz, I totaly agree with you!!

Dieselclacker

[nhgeezer]

The economy mode simply allows the transmission to up shift at a lower road speed and engine speed. This works well under no load conditions where you can up shift without lugging the engine. With a deisel engine lugging the engine, that is giving it more throttle without the engine responding by increasing RPM can damage the pistons. In a deisel direct injection fuel is injected into the cylinder in proportion to the throttle. Injecting more than the needed fuel is lugging. In normal mode the transmission will allow the engine RPM (revolutions per minute) to run higher before the transamission up shifts. Yep, it is great on flat ground with no load but if you start the rig in the morning and run the interstate for hours, it makes no difference because it acts only upshifting after slowing down or stopping and starting again.

Brad & Lucy aka the Geezer & the Hedgehog
1990 Foretravel with Detroit Deisel spinning an Allison
Kitty Kat: Earl
Whitey Ford the explorer riding the car trailer.
Navigation: CoPilot 9 lap top.
ASE Master technician
SAE

[AFChap]

Oldhiker

"Economy mode" changes the shift points in the transmission, causing it to upshifter quicker (at lower RPM) and to downshift slower (at lower RPM). The theory is that running the engine at lower RPM will save fuel. Most folks I know say it doesn't make a noticeable difference, a few claim it does.

[Pusherman]

The Economy mode on an Allison Tranny won't do anything while traveling on the strait and level. It does make a difference when traveling in hilly terrain. In this mode, the tranny will not downshift until engine RPM's reach a slightly lower level (maybe 100-200rpm's lower). This will provide slightly improved economy.

You will notice the coach slow down more before downshifting. I use it, and I do notice a differnce.

[rebelsbeach]

Don, I suspect your findings may indeed be the result of your coach being on a Freightliner chassis...

Most of the Newmar products are on Spartan chassis and as one reads in the Allison manual, the "mode" button acts on parameters specified by the chassis OEM, so it's quite possible that Freightliner actually dictates a more noticeable response.

I've not known or heard from many Newmar owners that share your findings, but then again.....I'm listening.

I have 17k on the LADB, as well as 4 or 5 I think on the Essex and I've never noticed any difference...

[clubmed98]

at homecoming this year at Spartan they indicated the economy mode is to be used in stop and go type situation and it changes shift RPM as noted and would keep rpms lower by shifting up quicker

[AFChap]

Yep, I have a Spartan chassis and note Economy mode does at Don describes. ...but had never heard the "to be used in stop and go" situation. Did they recommend not using it in highway cruising???