Retard switch

[Stephen_W]

My neighbor just bought a new 2013 Fleetwood Expedition 40X with a 360HP Cummings and Allison transmission on a Freightliner chassis. We were talking about the "Retard" button and he said the owners manual is vague about when to use it going down grades. Does anyone here have the same driveline? He'd like some do's & don'ts and what gear the tranny needs to be in when using the retard button vs grade, how it works, etc. Thanks in advance for the responses, just trying to help a friend out before he heads to the mountains.

[joraz]

I think some of the problem here is simply the word "retarder." It can be used as a generic term for different supplementary braking systems. For example, my last coach had a transmission retarder and my present coach has an engine compression brake. Both systems are referred to as retarders.

I hope the OP didn't send this thread to his pal. He'll be like in the Exorcist with his head turning 360 degrees.
jor

[dvg045]

Having operated charter buses over 25 years the retarder worked off the transmissiom once you engaged the retarder switch. The latest coaches had a small stick shift to downshift as you needed it to keep from overheating your brakes. Turn it off when you level off as it will overheat your transmission oil and in turn overheat the engine. Also, turn it off in the rain. I knew a driver that left it on on a curve while it was raining and when he backed off the acclerator the transmission downshifted and he lost control of the bus and wrecked. All in all they're a brake saver in the mountains. Good luck.

[JetAonly]

Wow, a whole basket full of knotted knickers on this one…….

Really isn't it a bit insensitive to be retarding your speed, shouldn't we be saying we are adding challenge to our speed? I mean really, would you like your transmission to be called retarded? Should we be so callous? tsk.

[wolfe10]

et2 wrote:

wolfe10 wrote:
Yup, very familiar with Allison retarders. I to a lot of mechanical inspections on Foretravels which do use the retarder.

But, rather than "he said, she said", as I posted above, please call Freightliner with your VIN and/or Allison with your transmission model number to get the FACTS.

I'm not sure what that experience has to do with the Fleetwood in question. I've posted documentation printed by the manufacture that should give some answers to your claims, other than the personal experience I've had with exhaust brakes and the now mentioned retarder on our exact model.

But in effort to resolve this issue I will be at he Fleetwood plant on Tuesday and will attempt to put his controversy to rest. I see you are claimed to be the Allison expert on other forums. I expect this will be a learning experience and help in further controversy on this subject.

Excellent. Thank you. Looking forward to getting the facts.

On edit: Fleetwood may be a good source for the facts-- they can probably look up for you the transmission model number/serial number as well as chassis information.

Probably best would be Allison (transmission serial number) with Freightliner (VIN) being a very close second.

[bfast54]

One VERY important DO NOT........I have not seen here........DO NOT use on Icy...Snowy Or Slick roads.......It will cause you....to have to change your shorts....possibly need the shower also.....:E...:W

[et2]

Stephen W wrote:
I'm the OP and the switch is labeled "RETARD" or "RETARDER" and is located in a row of switches just aft of the Allison transmission control pad. Thank you to all who posted the great suggestions and links. It is a big help and I will forward the link to this thread to my neighbor. Also, thanks to the poster for the Cummins spelling correction, that made a huge difference and I can sleep better now.

Yes, exactly where mine is. It is noted on the owners manual I posted on page 4-11.

[et2]

wolfe10 wrote:
Yup, very familiar with Allison retarders. I to a lot of mechanical inspections on Foretravels which do use the retarder.

But, rather than "he said, she said", as I posted above, please call Freightliner with your VIN and/or Allison with your transmission model number to get the FACTS.

I'm not sure what that experience has to do with the Fleetwood in question. I've posted documentation printed by the manufacture that should give some answers to your claims, other than the personal experience I've had with exhaust brakes and the now mentioned retarder on our exact model.

But in effort to resolve this issue I will be at he Fleetwood plant on Tuesday and will attempt to put his controversy to rest. I see you are claimed to be the Allison expert on other forums. I expect this will be a learning experience and help in further controversy on this subject.

[Stephen_W]

I'm the OP and the switch is labeled "RETARD" or "RETARDER" and is located in a row of switches just aft of the Allison transmission control pad. Thank you to all who posted the great suggestions and links. It is a big help and I will forward the link to this thread to my neighbor. Also, thanks to the poster for the Cummins spelling correction, that made a huge difference and I can sleep better now.

[wolfe10]

Yup, very familiar with Allison retarders. I to a lot of mechanical inspections on Foretravels which do use the retarder.

But, rather than "he said, she said", as I posted above, please call Freightliner with your VIN and/or Allison with your transmission model number to get the FACTS.

[et2]

http://www.allisontransmission.com/servlet/DownloadFile?Dir=publications/pubs&FileToGet=SA2953EN.pdf

[et2]

wolfe10 wrote:
To OP: Please call your chassis maker with your VIN and ask exactly what you have. Freightliner 800 385-4357.

As an alternative, call Allison with your transmission serial number:800 252 5283


With that Freightliner chassis, I have NEVER seen a transmission retarder, NEVER.

I showed you in the owners manual. I know what a "exhaust brake" is. This is not one. The switch specifically says "retarder". Do you own this exact model? Maybe Fleetwood put the wrong switch in two MH's? I doubt it.

Please see page 4-11 thru 4-14. There are two configurations. One showing a retarder switch ( as in the model we are referencing) and one with the exhaust brake.

http://fleetwoodrv.com/partsandservice/manuals/2013_DISC_EXPD_EXCR_PROV.pdf

[et2]

We Cant Wait wrote:
I mine turned on ONLY when I want to use it to help manage speeds going down a steep hill. A lot of towns have laws/ordinances against the use of Jake Brakes within the city limits. I've never seen the NEED to use it at speed less then 50MPH unless on a long steep grade.

It's not a Jake brake or a exhaust brake, so the ordinance wouldn't apply in this case. The whaamp clapping noise isn't associated with the transmission retarder. I use mine on exit ramps or pulling into rest stops, also when coming to a quick stop. The extra braking it provides is great for slowing down, sometimes with very little brake use.

[wolfe10]

To OP: Please call your chassis maker with your VIN and ask exactly what you have. Freightliner 800 385-4357.

As an alternative, call Allison with your transmission serial number:800 252 5283


With that Freightliner chassis, I have NEVER seen a transmission retarder, NEVER.

[slemnah]

It states "Engine braking: VGT"

VGT stands for Variable Geometry Turbo- that is the retarder that you have in your MH. It is similar to an exhaust brake in that it affects exhaust flow to slow the vehicle down. The vanes reverse or aperture closes (depends on engine manufacturer) to create back pressure with much the same effect as an exhaust brake.

http://cumminsengines.com/vgt-turbocharger


http://cumminsengines.com/uploads/docs/4971282.pdf

Steve