Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: dlkj07 on February 10, 2024, 10:47:15 am
Title: Retarder Glitch
Post by: dlkj07 on February 10, 2024, 10:47:15 am
Here's what's happening...
Normally when retarder is on and stick all the way forward (lowest setting) the retarder engages. Recently the retarder does not engage on its lowest setting but works on settings 2-6 just fine. It seems to be working in Auto mode (as far as I can tell)
Any ideas?
Could this be a physical problem with the lever itself?
Title: Re: Retarder Glitch
Post by: Bigoil76 on February 10, 2024, 10:58:11 am
Mine does nothing noticeable in the first, forward position, either. It operates in positions 2-6 I believe as it should, increasing in intensity as I pull it back to different positions. It is that way on my 99' U295 and also on my 08' 338 Nimbus. At times, in different driving conditions, I leave my retarder switch on and just move joystick as needed. With switch on and stick all the way forward I am able to leave cruise on without it kicking out on slight downhills. I just thought this is the way it was supposed to function. Am I wrong?
Title: Re: Retarder Glitch
Post by: Leonard on February 10, 2024, 02:08:28 pm
I read some owners say that there retarder increases as they pull back Our 98 u295 increases as you push forward #5257
Title: Re: Retarder Glitch
Post by: Pamela & Mike on February 10, 2024, 03:16:38 pm
I read some owners say that there retarder increases as they pull back Our 98 u295 increases as you push forward #5257
Leonard,
This is just how the rheostat switch has been installed. If you prefer the retarder to increase by pulling back on the handle just turn the rheostat around. Now this usually means pulling the mounting panel up so you can get to the back of the rheostat so you can make sure that the wires don't get pulled loose and there may not be enough room to just swivel it around without hitting another switch.
Mike
Title: Re: Retarder Glitch
Post by: dlkj07 on February 10, 2024, 03:31:09 pm
Mine does nothing noticeable in the first, forward position, either. It operates in positions 2-6 I believe as it should, increasing in intensity as I pull it back to different positions. It is that way on my 99' U295 and also on my 08' 338 Nimbus. At times, in different driving conditions, I leave my retarder switch on and just move joystick as needed. With switch on and stick all the way forward I am able to leave cruise on without it kicking out on slight downhills. I just thought this is the way it was supposed to function. Am I wrong?
Maybe I'm loosing it, I thought initially it was engaging with the lever all the way forward also...but maybe I'm remembering wrong and mine is working correctly. 🤷
Title: Re: Retarder Glitch
Post by: Michelle on February 10, 2024, 04:18:48 pm
Mine does nothing noticeable in the first, forward position, either. It operates in positions 2-6 I believe as it should, increasing in intensity as I pull it back to different positions. It is that way on my 99' U295 and also on my 08' 338 Nimbus. At times, in different driving conditions, I leave my retarder switch on and just move joystick as needed. With switch on and stick all the way forward I am able to leave cruise on without it kicking out on slight downhills. I just thought this is the way it was supposed to function. Am I wrong?
That's how it worked in our '03 U320.
ETA - I seem to recall a "nudge" of the joystick forward of the first position to make sure it's not active. Kind of a momentary action.
Title: Re: Retarder Glitch
Post by: Leonard on February 10, 2024, 04:58:47 pm
Really glad this coach my wife found has the retarder Works much better than the exhaust break on prevoius Monaco Windsor
Title: Re: Retarder Glitch
Post by: oldguy on February 10, 2024, 05:30:10 pm
On my coach the first notch of the joy stick slows the coach really well and the next 2 notches very little each one. I have to really concentrate to feel much difference. The rest is fine. When first got the coach I wanted the first notch to be less responsive and the next to be more. AS I use the Jake the most I'm fine now with how the retarder works.
Title: Re: Retarder Glitch
Post by: Bob & Sue on February 10, 2024, 06:49:44 pm
Our retarder still works on the first click ( or full forward ) position.. but, it's through the brake 3 stage activation mode. Which is the way I prefer because that way I don't have to keep turning the toggle switch on and off. And then the joy stick does its thing on the other 5 positions.
I did once leave it on and in the third position and could not figure out why the coach would noticeably slow down when I took my foot off the gas. Looked down and the joy stick was active. Moved the stick forward and back to normal,, yay.
Title: Re: Retarder Glitch
Post by: rusczyk56 on April 11, 2024, 10:34:30 am
In my case, a 2002 U320 with a 4000MH trans, per the book...
Retarder switch on/lever in position 0 (full forward) the "auto" feature of the retarder is regulated by brake air pressure from the brake pedal in three stages of about 1/3, 2/3 and full retardation. The lever is seven positions with full forward being off, but with switch on, in "auto" mode. From there, pulling the lever back through the next 6 positions (positions 2 through 7) results in manually controlled, increasing, no brake, no accelerator retardation.
A comment on the person reporting their stick is from bottom up, that's incorrect and was installed improperly. All retarder controls whether side panel mounted or column mounted are always "Top-Forward/Least to down-back/most".
I have read the Allision "big" service manual on the topic and there are clearly a myriad of possible TCM programming options that are dizzying. Allison refers all initial programming back to the vehicle OEM. What I have discovered over the years on my other coaches and from others is the OEMs have been very sloppy in ECM and TCM programing ranging from "as delivered default" programming to "really screwed up" programming. OEMs were/are supposed to, in conjunction with Allison and the engine builder create TCM/ECM programs that are designed around the vehicle and application. I can't repeat what an Allison tech support engineer said to me about that..... but I bet you can figure it out!
Then there is the whole Cruise Control/Brake Light thing.... another myriad of options.
I am in the hunt in the Tampa area to find an "old timer" Allison tech who truly understands the interactions of the TCM/ECM/Throttle/Brake/engine and is willing to "ride" with the computer to get mine set up as follows:
Change downshift pre-select ranges lessening 3-2-1 abruptness. Change throttle closed behavior to allow for coasting (plays into first item). Change Retarder "Auto" mode to be less aggressive (engage stage 1 and 2 at higher pedal pressures and ignore stage 3)
Problem is most of the current crop of techs are "book and computer" only thinkers and don't understand the interactions vs application and vehicle.
This problem is not only FT, but rampant throughout the MH world. I have friends with Wanderlodges. Newells, Prevost and other higher end SOBs (varying engines and ages) who with have struggled with the same issue, though the Prevost owners seem to have fewer complaints as most Prevost come to the outfitter very specifically built and configured for the use and builder.
As they say "we are not alone"!
As an aside, if you are not running the latest Transynd 668 version fluid, it's well worth the cost and pain to upgrade. I just did mine a couple months ago and two things I immediately noticed were lower temps and somewhat smoother shifts. Just watch for NAPA to have a 20% off sale....about $380 including tax in FL for two 5 gallon pails... Oh, what fun!
Title: Re: Retarder Glitch
Post by: Leonard on April 11, 2024, 02:53:00 pm
When I changed to TranSynd on previous Windsor I picked up 2 mph at same rpm
Title: Re: Retarder Glitch
Post by: dlkj07 on April 12, 2024, 10:58:21 am
In my case, a 2002 U320 with a 4000MH trans, per the book...
Retarder switch on/lever in position 0 (full forward) the "auto" feature of the retarder is regulated by brake air pressure from the brake pedal in three stages of about 1/3, 2/3 and full retardation. The lever is seven positions with full forward being off, but with switch on, in "auto" mode. From there, pulling the lever back through the next 6 positions (positions 2 through 7) results in manually controlled, increasing, no brake, no accelerator retardation.
A comment on the person reporting their stick is from bottom up, that's incorrect and was installed improperly. All retarder controls whether side panel mounted or column mounted are always "Top-Forward/Least to down-back/most".
I have read the Allision "big" service manual on the topic and there are clearly a myriad of possible TCM programming options that are dizzying. Allison refers all initial programming back to the vehicle OEM. What I have discovered over the years on my other coaches and from others is the OEMs have been very sloppy in ECM and TCM programing ranging from "as delivered default" programming to "really screwed up" programming. OEMs were/are supposed to, in conjunction with Allison and the engine builder create TCM/ECM programs that are designed around the vehicle and application. I can't repeat what an Allison tech support engineer said to me about that..... but I bet you can figure it out!
Then there is the whole Cruise Control/Brake Light thing.... another myriad of options.
I am in the hunt in the Tampa area to find an "old timer" Allison tech who truly understands the interactions of the TCM/ECM/Throttle/Brake/engine and is willing to "ride" with the computer to get mine set up as follows:
Change downshift pre-select ranges lessening 3-2-1 abruptness. Change throttle closed behavior to allow for coasting (plays into first item). Change Retarder "Auto" mode to be less aggressive (engage stage 1 and 2 at higher pedal pressures and ignore stage 3)
Problem is most of the current crop of techs are "book and computer" only thinkers and don't understand the interactions vs application and vehicle.
This problem is not only FT, but rampant throughout the MH world. I have friends with Wanderlodges. Newells, Prevost and other higher end SOBs (varying engines and ages) who with have struggled with the same issue, though the Prevost owners seem to have fewer complaints as most Prevost come to the outfitter very specifically built and configured for the use and builder.
As they say "we are not alone"!
As an aside, if you are not running the latest Transynd 668 version fluid, it's well worth the cost and pain to upgrade. I just did mine a couple months ago and two things I immediately noticed were lower temps and somewhat smoother shifts. Just watch for NAPA to have a 20% off sale....about $380 including tax in FL for two 5 gallon pails... Oh, what fun!
Thanks for the feedback, I did have Transynd put in when I first bought the coach a couple years ago. I'm not sure it made a difference since I had just purchased it, but my trans temps do run in the green most of the time...only rise when using the retarder heavily which is normal.
It would be nice to apply the changes you mentioned above, it's a great system but to have it refined so there's smoother transitions would make it perfect. 👍
Title: Re: Retarder Glitch
Post by: Leonard on April 12, 2024, 03:01:59 pm
I would also like someone like that to ride with me Our 1998 u295 goes through the first 5 gears real close then at 62 mph rpm's at 1850 which others have said is normal I guess I wish it was a seven speed I would rather cruise 62 at 1200 rpm's
Title: Re: Retarder Glitch
Post by: oldguy on April 12, 2024, 03:25:30 pm
The 8.3 engine wouldn't be happy at 1200 RPM. It would be too slow.