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Coasting Issue

Good Morning,
Retarder Joy stick is all the way forward, retarder switch is off, foot on accelerator traveling normal.  Foot off accelerator, transmission attempts to downshift to 2.  I must keep some pressure on accelerator to coast.  Very hard to do in city driving.  I removed large connector from Joystick and reconnected did not see anything loose or out of ordinary in console next to my left leg.  Normal operation has been that with the joy stick all the way forward, and retarder switch off, when I would remove foot from accelerator coach would coast until I touched brake or switched retarder on.  This started just before we left from our two month trip.  Guess I should have done something about it earlier but I adjusted my driving to compensate.  Using the cruise control as much as possible helped and learning to keep just enough pressure on accelerator to keep transmission from trying to downshift.  I have done a ton of searching and reading the forum but have not been able to find this issue discussed.  So I am asking for help now.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #1 –
Is shift selector pad in normal or economy? My will shift more frequently in normal. Economy seems to hold it up a bit both up shifting and down.
Scott

Re: Coasting Issue

Reply #2 –
If the on/off switch and the lever were installed to work in the opposite directon from what we are used to, that would produce your situation.  You might turn the switch the opposite way and pull the lever all the way back and see what happens.  Just a thought but the down shift to second says the retarder is ON and the lever is at max retard.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Coasting Issue

Reply #3 –
Quote from: Rudy –
If the on/off switch and the lever were installed to work in the opposite directon from what we are used to, that would produce your situation.  You might turn the switch the opposite way and pull the lever all the way back and see what happens.  Just a thought but the down shift to second says the retarder is ON and the lever is at max retard.
The on/off switch works normally.  Lights up red when on and active.  'retarder works normally when switch is on and lever is moved back to one two or three.  Retarder heats up normally in use.  Coach just will not coast unless I select neutral.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #4 –
Quote from: dsd –
Is shift selector pad in normal or economy? My will shift more frequently in normal. Economy seems to hold it up a bit both up shifting and down.
Scott
Normal and Economy work normally. as Brett Wolfe has so eloquently described.  Symptom occurs in both modes.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #5 –
Does your retarder temp fluctuate normally as you accelerate and decelerate or stay hot? Wonder if the solenoid on the accumulator could be sticking.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: Coasting Issue

Reply #6 –
Herb, you are welcome to come see me on east side of Houston.  I have an Allison Guru that will solve it
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Coasting Issue

Reply #7 –
Quote from: Elliott –
Does your retarder temp fluctuate normally as you accelerate and decelerate or stay hot? Wonder if the solenoid on the accumulator could be sticking.
We drove over the Smokies twice back and forth.  Retarder works normally, heating up while active and on, cooling down when I turn the switch off.  As Rudy says it acts like the switch is on.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #8 –
Quote from: Rudy –
Herb, you are welcome to come see me on east side of Houston.  I have an Allison Guru that will solve it
Thanks Rudy, I am in Houston until I return to coach Friday.  I may very well do that.  I will call you.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #9 –
On my coach the retarder doesn't have anything to do with the trans shifting to 2. I wonder if
they changed that in the newer coaches. When I put the Jake brake in I found the wire under the
dash so I could hook it up to a floor switch so I could use it for the Jake. It was # 9 wire in the
trans computer.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Coasting Issue

Reply #10 –
Does your display that you are using to read retarder temperature also show gear selected and actual gear position? Would be curious if when your in fifth gear it is requesting 2nd gear on display. This is not displayed on your shift panel. I don't believe this is related to your retarder in any way.

Re: Coasting Issue

Reply #11 –
Quote from: dsd –
Does your display that you are using to read retarder temperature also show gear selected and actual gear position? Would be curious if when your in fifth gear it is requesting 2nd gear on display. This is not displayed on your shift panel. I don't believe this is related to your retarder in any way.
I have a Silverleaf that shows gear selected and gear attained and mode 1 (power) or 2 (economy).  When I let off of the accelerator the display shows 2 5 or 6 as I continue to slow the second number or attained continues to drop until I stop.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #12 –
Sounds like it is actively seeking second gear. Mine will do that if I have the normal mode selected but doesn't in economy. Sounds like the shift programming has changed. Drivable but yes annoying. Rudy's  tech should be able to resolve

Re: Coasting Issue

Reply #13 –
Poor Boy Glass Dash

https://www.foreforums.com/index.php?action=dlattach;sa=tmpattach;attach=post_tmp_6845_bb22089d3a9387cf554526f7b3341947;topic=45182
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #14 –
On the way back to Livingston, This happened twice.  Set cruise control to 62 mph and Mode 2 and after a time, the transmission acted like I turned the key off.  Cruise control went off and mode went to 1.  I reset cruise to 62 and clicked Mode 2.  After a time it happened again.  I reset cruise to 59 and Mode 2 and it never happened again for the next few hundred miles.  Possibly related, but do not know.  Loose or corroded ground? Some where? 
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #15 –
Quote from: Herb Stark –
  Loose or corroded ground? Some where? 

That's the most likely culprit IMO.  I would start there. 
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Coasting Issue

Reply #16 –
Update on coasting issue.  Got Lewis Large (On rec. from Rudy) to come take a look.  Lewis only works in the evening and night.  So he came and put his computer on my data port after disconnecting my Silverleaf.  Determined that Retarder and switch was working normally.  After hearing my symptoms he decided that he needed to check a solenoid that was in the valve body.  He took all of that apart and installed solenoid even though upon disassembly determined that the old solenoid was working ok at the time.  New gaskets and salvaged most of fluid to return to transmission.  Lewis had a pump to restore fluid, but the batteries were down and needed some D cells which neither of us had.  So he buttoned things up an left for two days.  While he was gone I got some D cells and pumped the fluid back into transmission.  When he returned, he checked some pressures and removed gauges from transmission.  We went for a test drive, and no improvement.  Could not tell for sure but it seemed to shift smoother, but still would not coast.  It did not seem to be as much of a problem as it was on my trip.  However I figured out that the coasting problem is much more obvious when I am pulling my Jeep Grand Cherokee at 5K lbs.  No problem towing it, just hat when I want to coast it brakes much harder with Jeep in tow than without.  Makes sense when you think about it. At the point Lewis left and planned to bring another transmission ECU to try.  Upon his third trip to my coach, Lewis replaced the ECU with a rebuilt one.  We took another test drive and the transmission would still not coast.  Lewis did some more checking and noted that the Engine ECU told him that the Jake brake was on.  Of course I do not have a Jake brake, I have a retarder system which is working properly.  The light comes on the switch and Joystick adds increasing retardation as moved rearward.  Lewis felt that he was at the end of his ability to find the problem, except for the Jake brake indication which would require another skill set to run down.  So he contacted Jason Cantrell at Mid Coast Engine Transmission Inc in Houston TX.  He suggested that I bring my coach in to him.  He felt like he could solve the issue.  One thing we surmised is that Foretravel put a Jake Brake signal wire in the ECU harness that may have rubbed against a clamp or brace and shorted out to ground which maybe sending the transmission a signal to not coast because it expected a Jake brake to be engaged.

At this point Lewis Large of Expert Transmission (Allison Trash Trucks) gracious has not charged me a penny for 3 trips and much work.  He refused to accept payment for not solving my problem.  He does agree I have a problem so he is sending me another shop.

We are currently at Gone Fishing RV Resort and upon our return to Livingston Monday, I have spoken to Jason and we have a tentative appointment with Mid Coast for Tuesday AM.  The search for a solution goes on.....stay tuned.
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #17 –
With the computer saying the Jake brake is on that would tell the transmission to shift down to
what ever gear the computer is programed to shift to and from your description I would say it is
second gear. When I was hooking up the Jake I installed, I found the wire under the dash that
would do that. It will only activate with no throttle and if cruise is on it won't come until I get the
cruise off or I'm 5 miles an hour above the speed I set the cruise at which was set by Cummins.
I believe that the wire is grounded for it to call for 2nd gear. I hope this helps.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Coasting Issue

Reply #18 –
That make perfect sense seeking to downshift. Workaround may be pulling that wire were in goes into ECU

Re: Coasting Issue

Reply #19 –
Quote from: oldguy –
With the computer saying the Jake brake is on that would tell the transmission to shift down to
what ever gear the computer is programed to shift to and from your description I would say it is
second gear. When I was hooking up the Jake I installed, I found the wire under the dash that
would do that. It will only activate with no throttle and if cruise is on it won't come until I get the
cruise off or I'm 5 miles an hour above the speed I set the cruise at which was set by Cummins.
I believe that the wire is grounded for it to call for 2nd gear. I hope this helps.

Yes, that confirms what I suspected.  Now to just find that wire and disable it or find the how it has suddenly found a ground.  Maybe the engine wiring diagram will have a PIN number from the ECU plug.  Thanks guys
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #20 –
Here is picture of the Allison wire/connector chart. The downshift wire is #11. I was wrong when
I said # 9 in a previous post. The picture is where I connected to the same wire to go to the switch
I put in. I hope this  legible as I couldn't figure out how to scan it to this computer.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Coasting Issue

Reply #21 –
I will try later to figure out how to send the scanned copy as the copy I sent isn't very clear.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Coasting Issue

Reply #22 –
The yellow wire to yellow wire is the connection I made.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Coasting Issue

Reply #23 –
Quote from: oldguy –
I will try later to figure out how to send the scanned copy as the copy I sent isn't very clear.
I can read it though thanks
Herb and Willie
Escapees 90802
2014 IH-45 Build 6581
2002 U320 40' AGDS Build 6021 Sold
1999 U320 36' No Slides Sold
2007 Monaco Dynasty Diamond IV Sold
2005 Discovery 39 Sold
1986 20' Wilderness TT,  Died a natural death after floods, etc.
Walldog's Journeys
And Willie Said

Re: Coasting Issue

Reply #24 –
I am trying again
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport