Retarder switch?

[flaggship1]

Originally Posted by Smitty77

I sure could be wrong, but suspect that your coach does not have a transmission retarded. Labeled that way, and it is a retarded of speed, but probably a exhaust brake.

What engine, as that would probably help confirm Exhaust vs Compression brake assist.

Best,
Smitty

I have the lowly '08 Fleetwood Bounder with ISB 325 HP T - and Allison 3000 MH. I could be as wrong as you - but I am pretty certain that what I have is not only labeled as you say "Retarder" but actually is a Allison Transmission Retarder and not an exhaust brake. As for what the OP has - we shall see. No reason to suspect more than a Tranny Retarder based on profile and surely no reason to believe no tranny Retarder that I know of. But I am never surprised when I an wrong!

[John S.]

My transmission retarder has a 6 postion Joystick and the coaches that have just the button can have that installed too. It is not a jack or compression brake. You will have 3000R for a transmission on the new transmissions and on the old ones it is a 3066 number.

[John S.]

Also it will activate with the brake too. SO the first part of the brake pressure will put on the retarder in 2nd position and fully engaging the brakes will put the retarder on fully.

[rexabbot]

Isn't that when the DW tells you to slow down on the mountain passes?

[botiemad]

I wouldn't be without it. My coach has 260,000 miles on the original service brakes and a recent inspection showed less than 40% pad wear. Love that PacBrake.

[Tom222]

Originally Posted by John S.

My transmission retarder has a 6 postion Joystick and the coaches that have just the button can have that installed too. It is not a jack or compression brake. You will have 3000R for a transmission on the new transmissions and on the old ones it is a 3066 number.

Mine is just a google switch, off or on.

I am new to the RV world and really worry about driving in the mountains, epically down steep hills.

Tom

[Libero]

Originally Posted by Tom222

Mine is just a google switch, off or on.

I am new to the RV world and really worry about driving in the mountains, epically down steep hills.

Tom

Tom

What is a "google" switch. LoL I think a typo and you missed the "t" it is right above the "g" :-)

Or do you really have a "google" switch.

[Tom222]

Originally Posted by Libero

Tom What is a "google" switch. LoL I think a typo and you missed the "t" it is right above the "g" :-) Or do you really have a "google" switch.

Sorry I meant toggle switch , I am tired, and mis-spelled it and spell check corrected it to google....

[Libero]

Originally Posted by Tom222

Sorry I meant toggle switch , I am tired, and mis-spelled it and spell check corrected it to google....

It is easy to do, I don't think anyone thought it was otherwise and the t is just above the g on the keyboard. I just got a chukkle out of it. I usually read/post Irv2 on my phone or tablet and no spell checker on the app. I make a lot of typos.

[davidlgood]

The ONLY production motorhome that includes an Allison Retarder is a Foretravel. No Fleetwood (or REV Group RV manufacturer -- such as Monaco, American Coach, etc.) included an Allison Retarder. Even though the buttons may claim "Retarder"... they're misusing the word to mean an engine retarder of some sorts -- almost always an exhaust brake on Fleetwood models. An Allison Retarder has to have an Allison Transmission DESIGNED with the retarder in mind -- it is a VERY EXPENSIVE retrofit, which is why you'll likely never see it out in the wild as an after-market purchase.

When you engage your engine brake (retarder) you will see the Allison Transmission "call" for Gear 2 and the exhaust brake will engage and the command ("call") to downshift will take place. Downshifting has nothing to do with what an Allison Retarder does. An Allison Retarder essentially shoot transmission fluid at the output side of the transmission to restrict movement and slow things down. Almost no noise involved with the Allison Retarder. If your Bounder kicks into a lower gear and revs up considerably when you apply that "R" button... you have an exhaust brake and the only thing the Allison transmission is doing is calling for a downshift pattern to get safely to Gear 2.

I realize this reply is a decade after the original post -- but as it was never settled/clarified in the various posts I'm putting this information here for those who might be searching for answers.

[Skip426]

Originally Posted by davidlgood

I realize this reply is a decade after the original post -- but as it was never settled/clarified in the various posts I'm putting this information here for those who might be searching for answers.

David ; the question about the mislabeled " Retarder ( RTDR ) " switch comes up often and requires those that know to correct; using our knowledge of transmissions and availability; the misconceptions.

At least Newmar ( back in the day when my coach was built ) put a label on the dash , beside the RTDR switch , that says " Exhaust Brake ".

I missed the question when this thread was new , and now see that flagship1's, Retarder switch is most likely an on/off for the exhaust brake function of his engines VGT ( Variable Geometry Turbocharger) .

[BirdDoggin]

http://svfd.net/SVFD%20Files/Article...0It%20Work.pdf

The transmission retarder appears to work better than a Jake Brake with little noise or wear. I am assuming that they are much more expensive than an exhaust or engine brake or else ever coach would have one.

[Skip426]

I can't com up with a price difference , on Allison transmissions with/without the optional hydraulic retarder .

But from my 1999 Allison transmission manual , the transmission series information an tag on the side of the unit , would contain an " R " preface or suffix. EG ; R 5000 or 4000 R

From pictures available online the retarder housing on the back of the transmission is easily identifiable , adding 5"+ to the length of the trans.