Allison Retarder switch

Topic: Allison Retarder switch (Read 2653 times) previous topic - next topic

Allison Retarder switch

December 03, 2015, 11:12:31 pm

We have the MD3060R with the rocker switch (no joystick)
My question is....... without the joystick, is there a modification that allows the use of the retarder on downhill grades without having to keep the service brake pedal activated? I don't like riding the brakes for very long. I have always applied the brakes firmly to slow to a safe speed and rpm, then let up until rpms build back up, letting the brakes cool in between. This is in our F250 powerstroke pulling our 30ft TT.

Last week in the coach while coming down the grade on I26 out of Asheville, I had to keep the pedal depressed to keep the retarder active. It's my understanding that this is normal.

Is there a less expensive mod other than the six step joystick? I'm OK with the 3 step brake pressure switches and rocker if it would stay engaged.

Justin

Re: Allison Retarder switch

Reply #1 – December 03, 2015, 11:27:11 pm

I have found on most grades that using the transmission gearing is quite effective to "hold" the coach back and the need for constant braking or retarder use is often eliminated. It's the angle of the dangle type of thing. Balance between speed and engine rpm. JMHO

I am probably wrong in making this statement but I believe that the retarder is to be used for short periods of time. If used too often or continuously the temp of the retarder might rise too high and the retarder will shut down and might be damaged. Allison Retarder Temperature

I always watch our retarder temp. on the vmspc so it doesn't get tooooooo hot.

Re: Allison Retarder switch

Reply #2 – December 04, 2015, 07:11:15 am

Quote from: Carol & Scott – December 03, 2015, 11:27:11 pm

I have found on most grades that using the transmission gearing is quite effective to "hold" the coach back and the need for constant braking or retarder use is often eliminated. It's the angle of the dangle type of thing. Balance between speed and engine rpm. JMHO

I am probably wrong in making this statement but I believe that the retarder is to be used for short periods of time. If used too often or continuously the temp of the retarder might rise too high and the retarder will shut down and might be damaged. Allison Retarder Temperature

I always watch our retarder temp. on the vmspc so it doesn't get tooooooo hot.

The above procedure is the way I used our 1997 U320; down-shifting the transmission into a lower gear for braking going down a slope with intermittent use of the brakes to slow further if needed in curves of the road, etc. Watch those temperatures!

Re: Allison Retarder switch

Reply #3 – December 04, 2015, 07:17:57 am

Quote from: FourTravelers – December 03, 2015, 11:12:31 pm

Is there a less expensive mod other than the six step joystick? I'm OK with the 3 step brake pressure switches and rocker if it would stay engaged.

The joystick is really the best way to control the retarder. The joystick is easily moved between its several positions and that smoothness of operation works extremely well. If you can get one for around $500 then I would consider that money extremely well spent.

Re: Allison Retarder switch

Reply #4 – December 04, 2015, 08:14:35 am

Gearing into slower speeds downhill (same as the one going uphill especially if it's a steep hill/mountain) & keeping a vigilant eye on both transmission & engine temps + an occasional firm hit on the service brakes will get you thru most anything, but the joystick is a great add-on (mine came with it originally) so the $500 would be well worth it.

This from a relative newbie (& a chick to boot) who just learned recently how to do it right after a near 'emotional breakdown' on a long 7% grade....can't beat the combination of the 3 together, your confidence will soar & you'll be driving more safely & saving your brakes as well.

Re: Allison Retarder switch

Reply #5 – December 04, 2015, 08:33:32 am

I thought I read on the forum that with the rocker switch version the first position of the retarder activates when you remove
your foot from the accelerator pedal.Can easily be checked next time we drive coach.

Re: Allison Retarder switch

Reply #6 – December 04, 2015, 08:58:11 am

My coach has both, and as I remember the switch gives three stages of resistance depending on brake pressure, nothing when you back off the throttle. On the joy stick the first position is off, then the next operates when you back off the throttle and further positions just more resistance as you move the stick.

Re: Allison Retarder switch

Reply #7 – December 04, 2015, 09:54:44 am

Will take coach out to warm up to change trans and gear oil,will test retarder then.All you have to do is turn rocker switch on
and coast and see if the light comes on during that coasting.Not sure but maybe different years of rocker switch retarders
are wired differently.

Re: Allison Retarder switch

Reply #8 – December 04, 2015, 10:07:51 am

Quote from: craneman – December 04, 2015, 08:58:11 am

My coach has both, and as I remember the switch gives three stages of resistance depending on brake pressure, nothing when you back off the throttle. On the joy stick the first position is off, then the next operates when you back off the throttle and further positions just more resistance as you move the stick.

Ours operates just as you have described it.

Re: Allison Retarder switch

Reply #9 – December 04, 2015, 11:30:51 am

Not having a retarder, I am listening to this discussion thread with great interest. Pertinent to the most recent entries, I have often wondered if constantly using the retarder, especially around town, has a adverse impact on fuel mileage. One of the more useful "hypermiling" techniques (which I try to practice) is to accelerate to the desired speed, then "coast" as much as possible. It sounds to me like the "joy stick" retarder, if left "ON" (step 1 or 2) all the time, would not allow this driving mode. You would either have to be accelerating, or else maintaining your desired speed with some amount of throttle, between stops. The "switch" activated retarder, on the other hand, sounds like it would allow free coasting between stops, while still being instantly available when the brakes are applied. In this respect, it would seem to be a more "economical" option.

Any comments from actual users?

Re: Allison Retarder switch

Reply #10 – December 04, 2015, 11:36:55 am

Selecting "on" immediately applies retarder when you lift off throttle. Handy for garbage trucks in the city. RV? Not so much, and economy will suffer

Re: Allison Retarder switch

Reply #11 – December 04, 2015, 11:50:42 am

In medium crowded freeway traffic in Southern California I do use the retarder. Normally set at position #2 on the controller.

Guru buddy moved mine to the second row up from the bottom on the left hand console which fits my seating position very well.

Mine seems different as mine had been installed to have the lever move forward to increase its operation not back.

In seeing posts about the retarder operation that mentions downshifting to increase its effectiveness I always thought the retarders operation was not engine rpm connected.

Of course downshifting the motor to increase its compression braking is helpful and may be part of the engines abd trans programming as a help but my dim memory is the retarder is a seperate piece on the rear of the trans?

Re: Allison Retarder switch

Reply #12 – December 04, 2015, 12:19:17 pm

Quote from: Tim Fiedler – December 04, 2015, 11:36:55 am

Selecting "on" immediately applies retarder when you lift off throttle. Handy for garbage trucks in the city. RV? Not so much, and economy will suffer

Yup, eliminates my favorite "gear"-- COASTING!

Re: Allison Retarder switch

Reply #13 – December 04, 2015, 12:46:15 pm

Quote from: Chuck & Jeannie – December 04, 2015, 11:30:51 am

Not having a retarder, I am listening to this discussion thread with great interest. Pertinent to the most recent entries, I have often wondered if constantly using the retarder, especially around town, has a adverse impact on fuel mileage. One of the more useful "hypermiling" techniques (which I try to practice) is to accelerate to the desired speed, then "coast" as much as possible. It sounds to me like the "joy stick" retarder, if left "ON" (step 1 or 2) all the time, would not allow this driving mode. You would either have to be accelerating, or else maintaining your desired speed with some amount of throttle, between stops. The "switch" activated retarder, on the other hand, sounds like it would allow free coasting between stops, while still being instantly available when the brakes are applied. In this respect, it would seem to be a more "economical" option.

Any comments from actual users?

There is no need to leave the joystick in any "on" position. I normally leave the rocker switch in the "on" position and the joystick far forward (or "off"). This allows free coasting when the accelerator is released, and yet the joystick is readily available for smooth deceleration without use of the service brakes when desired. The service brakes are required to come to a complete stop, but the joystick-controlled retarder will provide nearly all of the deceleration.

To me, at least, it's a highly-desirable setup. I wouldn't want to be without it!

Re: Allison Retarder switch

Reply #14 – December 04, 2015, 01:09:02 pm

Am I the only one who actively selects the retarder joystick position pretty much all the time?

Normal operation in our coach.

Retarder switch is on by default. (I really don't see a reason to turn it off)

It stays on with the joystick in 0 for light traffic freeway driving. The coach will coast just fine in this mode and it engages just like the service brakes.

Joystick in position 1: Used in light traffic on the freeway and low speed stop and go. The throttle acts as an on/off switch or coast controler.

Joystick position 2/3: Used as above but in heavier traffic. Again this is stop and go type stuff when you want instant control.

Joystick 4/5: Active hill descents or high effort braking.

My left hand is on the wheel or the stick and a lot of times back and forth in quick succession. I have No reservation about selecting full engagement at any time for any length of time. Put it another way, would you rather have your transmission fail from high temps on a long downhill or your service brakes.
I really think that folks are a bit to worried about the 4000 series Allison's that most of us have. That is a severe service transmission with literally an unlimited GVW rating from Allison. Are there any documented failures from over use in our application? I believe the only way to hurt one would be with dirty fluid...

And to frame this up I had the unfortunate experience of bailing out of a Mack at 50MPH a few decades ago on a long downhill that turned into an uncontrolled decent... Never want to have that opportunity again!

Re: Allison Retarder switch

Reply #15 – December 04, 2015, 01:40:36 pm

Quote from: squeezer – December 04, 2015, 01:09:02 pm

Am I the only one who actively selects the retarder joystick position pretty much all the time?

No..

Re: Allison Retarder switch

Reply #16 – December 04, 2015, 02:20:29 pm

Quote from: squeezer – December 04, 2015, 01:09:02 pm

Am I the only one who actively selects the retarder joystick position pretty much all the time?

I don't want this to be taken the wrong way, but I'm another active joystick user.

Re: Allison Retarder switch

Reply #17 – December 04, 2015, 02:21:53 pm

I use my retarder like you do Squeezer all the time. I have Amsoil Torque Drive synthetic fluid in my tranny and I do watch the temps on my VMS-PC. I love it and it works great combined with proper gearing coming down mountains and watching speeds and temps. It is one big reason for my getting our Foretravel...........

Re: Allison Retarder switch

Reply #18 – December 04, 2015, 03:01:00 pm

And, some of us use the Allison the same way. Motorhomes are the ONLY automatic transmission vehicles we have ever owned. So, I am glad the Allison 3000 and 4000 allow you to pretty much choose what YOU want.

WHY??? Well, pure physics dictates that a transmission is REACTIVE, reacting to what happened behind you. And the heavier the vehicle the more the momentum, the further behind you it is.

But, a driver can choose to be PROACTIVE. Again this is a choice-- I have no problem with those who just use "D". But a driver can see what is happening in front of him. Downshift earlier if a steep grade is coming up, Downshift and hold it in the lower gear for descents. And by using the mode button AND the up/down arrows, pretty much choose the gear you want to be in.

Re: Allison Retarder switch

Reply #19 – December 04, 2015, 03:47:07 pm

Quote from: wolfe10 – December 04, 2015, 03:01:00 pm

And, some of us use the Allison the same way. Motorhomes are the ONLY automatic transmission vehicles we have ever owned. So, I am glad the Allison 3000 and 4000 allow you to pretty much choose what YOU want.

WHY??? Well, pure physics dictates that a transmission is REACTIVE, reacting to what happened behind you. And the heavier the vehicle the more the momentum, the further behind you it is.

But, a driver can choose to be PROACTIVE. Again this is a choice-- I have no problem with those who just use "D". But a driver can see what is happening in front of him. Downshift earlier if a steep grade is coming up, Downshift and hold it in the lower gear for descents. And by using the mode button AND the up/down arrows, pretty much choose the gear you want to be in.

So to clarify, you use gear selection and engine braking alone or gear selection plus retarder?

The old trucker adage that you go down the mountain in the same gear you go up the mountain doesn't work for me as we can go up at a much faster rate than I am comfortable going down...

Re: Allison Retarder switch

Reply #20 – December 04, 2015, 04:03:10 pm

For descents, my preference is to use gears, retarder and brakes in that order of preference and almost always a mix of all. A lower gear gets you engine braking and higher RPMs which means better cooling. Add in a notch or two or retarder for some additional braking force. Too much retarder because you are at a higher gear just means higher retarder temps. The same downhill speed can be maintained at a lower gear and a bit less retarder and you will manage retarder temps better. It is a balance that comes with some experience. No reason at all to be in a hurry coming down the mountain. Your safety and comfort level should always dictate speeds. If you need to use the air brakes apply them firmly until you have slowed to the speed you want and then release them. Don't ride the brakes. If I am coming up to a curve going downhill those big orange speed signs are my max speeds for my coach. Slow down before you get to the curve. I think you will have better control through the curve if you are not braking.

I use the retarder switch on in traffic for more aggressive braking if I need it.

Do what works for you. Find out what that is. Your safety and comfort level should always be your guide.

Re: Allison Retarder switch

Reply #21 – December 04, 2015, 04:23:59 pm

Quote from: squeezer – December 04, 2015, 03:47:07 pm

So to clarify, you use gear selection and engine braking alone or gear selection plus retarder?

The old trucker adage that you go down the mountain in the same gear you go up the mountain doesn't work for me as we can go up at a much faster rate than I am comfortable going down...

Depends on what auxiliary braking the coach has. But, yes, gears in combination with exhaust brake, engine compression brake or retarder.

Re: Allison Retarder switch

Reply #22 – December 04, 2015, 05:06:29 pm

As Roger says and in that order.
Get slowed up before the curve and don't brake halfway around it.
Brian.

Re: Allison Retarder switch

Reply #23 – December 04, 2015, 05:22:12 pm

If you always use the retarder the brakes tend to glaze. In a low traction emergency which is obviously rare the retarder is supposed to be turned off.

I like playing with the disk brakes. Keeps me aware of the coaches limitations. Warmed up and deglazed they are almost race quality.

If they do not stop well then that to me would be a signal to have them inspected.

Lots here have reported corroded brake pins and irregularly worn pads because of it.

The retarder can cover up brake issues in my experience.

After having driven countless SOB's with average brakes and a somewhat limited capacity engine or exhaust brake the meritor disks are much safer.

Unfortunately designed for much heavier vehicles so they tend to glaze up and not be at operating temp in normal use.

Most here used to leave their retarder on always. I am glad to see some owners exercising the brakes.

My brakes used to not release completely from over greasing and/or dirty pins. Redoing them several times($$$) and adding the helper springs has so far reduced this to zero.

Plus regular hard use during any drive.

Re: Allison Retarder switch

Reply #24 – December 04, 2015, 08:00:26 pm

Quote from: Caflashbob – December 04, 2015, 05:22:12 pm

If you always use the retarder the brakes tend to glaze. In a low traction emergency which is obviously rare the retarder is supposed to be turned off.

I like playing with the disk brakes. Keeps me aware of the coaches limitations. Warmed up and deglazed they are almost race quality.

If they do not stop well then that to me would be a signal to have them inspected.

Lots here have reported corroded brake pins and irregularly worn pads because of it.

The retarder can cover up brake issues in my experience.

After having driven countless SOB's with average brakes and a somewhat limited capacity engine or exhaust brake the meritor disks are much safer.

Unfortunately designed for much heavier vehicles so they tend to glaze up and not be at operating temp in normal use.

Most here used to leave their retarder on always. I am glad to see some owners exercising the brakes.

My brakes used to not release completely from over greasing and/or dirty pins. Redoing them several times($$$) and adding the helper springs has so far reduced this to zero.

Plus regular hard use during any drive.

I take it not all Foretravels have 4 wheel disc brakes? The 1999 U320 has them

Affiliate Notice