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Topic: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful (Read 22349 times) previous topic - next topic

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #20 –
I would try RICK's suggestion of heating the control pad. My coach has this problem when the pad gets cold.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #21 –
Quote from: Rick –
Robert
take a hair drier to the shift pad and warm it up a bit if the coach is cold, it may be related to the shift pad being cold.
Good luck,
Rick

Gave it a try but it didn't do anything.  I'm willing to try anything at this point though.

I've been having an erratic issue with the Level System Alarm coming and going after the Kansas snowstorm and I'm starting to wonder if this has anything to do with possibly being a Shift Inhibitor function.  I pulled over and checked out all of the airbags and couldn't find any reason why the LSA lit up the first time and it certainly didn't cause the Allison to lock me out at that time and it went away.  The LSA alarm would come and go for seemingly no reason as I continued to drive for the next 8 hours or so and didn't stop my traveling but it has lit up recently and doesn't seem to be going away (as mentioned, I can't find any actual issues with the leveling system).  It hasn't lit up until this last time that I started the engine to keep the batteries up since the Powertech/Isuzu genet is such a drama queen when it gets cold. 

I guess I'll open up the controls for it and try to clean it all up this morning before I call in someone from the Allison repair shop 20 miles away.  For all the breakdown possibilities that I had considered before traveling, a transmission that won't shift out of neutral was not on the list. 

caflashbob, 
I disconnected everything and shut off the master disconnect switch while I was changing out the batteries for 30 minutes or so but the flashing 6 and R were right back when I started up the engine. 

Thank you all.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #22 –
Robert when I had my problem I did not have to reset anything.By putting the trans in gear as soon as the engine started the engine was at a lower RPM so the trans would shift. It sounds like you have a different problem if you are at 700 RPM. Mark

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #23 –
When I was having Allison problems I was told to use a hairdryer to warm the ECU.  I did this for several days til I could get to an Allison shop and it worked.  I then sent the ECU to John ? in Texas and he rebuilt it.  I can't recall the company name right now.
Gary B

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #24 –
866 439 9779 John Kopalek

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #25 –
My Allison ECU is on the rear wall of the water pump compartment.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #26 –
Robert,

About the only thing not mentioned so far is check the transmission fluid level.  If low, no shift.

Seems the last resort is a tow to a Allison shop that can scan the computer to see what is what.

All the best.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #27 –


Robert,
I don't see mention of your having verified that the King Throttle Control unit is working properly.
I keep going back to your problem onset where you had driven a long way in wet, nasty conditions.  Then the transmission wouldn't shift out of neutral.
The Allison requires RPM and other "Shift Permissive" information from the King Controls Unit in order to allow a shift from neutral to "R" or "D".  Once in gear, it requires different information; throttle POSITION sensor and BRAKE LIGHT FILAMENT resistance to GROUND in order to allow more than a "limp-home throttle setting - generally = 1100 to 1200 RPM for the 8.3.
I know that you have lowered the idle RPM, but the Allison still may not have that information due to a connection being momentarily or permanently open in the wiring from the King Control Unit to the Allison (For an onset occurring during operation in snowstorm conditions -- highest probability place being a plug connector).
Right at the King Control unit (for those that do not know - engine side-rail, curb side) , there are several "Plug and Play" wire plug connections.  These are pretty nicely designed to exclude moisture and the elements.  However, I have found that they sometimes don't stay seated firmly.  I have separated them, inspected, cleaned, dielectric greased, reseated and then tie-wrapped them firmly together to prevent re-occurrence of a failure to shift out of neutral (one time)  and a failure to respond to throttle position (a second time). I've attached a couple of the King Controls Unit Wiring diagrams, in case you don't have them.
Good luck, best wishes and keep us posted.
Neal

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #28 –
Quote from: wolfe10 –
866 439 9779 John Kopalek

I was able to talk to him earlier and was able to use the "hit the Drive button before the engine reaches idle from a start" to limp home.  But this is not fixed.  You cannot shift to neutral or else it reverts back to the blinking 6 and R.  You have to shut the engine down and restart every time.

The transmission is shifting very aggressively, holding gears nearly up to redline and won't actually shift up into 6th gear from 5th, even at 70 mph. 

The weather is supposed to warm up here over the next few days and I am going to hose off the underbody and engine compartment which will hopefully reveal something that I have missed. 

I will keep you updated with what I find.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #29 –
I wonder what would happen if you used the MODE Allison shifting routine.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #30 –
Recheck for diagnostic codes.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #31 –
On mine I found that if I did not have full battery voltage the transmission would go into default mode. I could then drive but it would not shift into 5th and I was limitred to 45MPH.  Properly charged batteries solved it.  As a quick fix try leaving the boost switch on.  Just a thought.
Gary B

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #32 –
Quote from: Neal Pillsbury –

Robert,
I don't see mention of your having verified that the King Throttle Control unit is working properly.
...
Good luck, best wishes and keep us posted.
Neal

I would echo Neal's offering.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #33 –
Last year had same problem. Mine was related to the battery terminals. Cleaned. No problems since. Mine even sent itself into reverse at a red light and quickly started backwards. If that doesn't scare you then nothing will....

The other occasion was a slide out issue as earlier mentioned.

Good luck.

David

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #34 –
Quote from: dwest –
Mine even sent itself into reverse at a red light and quickly started backwards. If that doesn't scare you then nothing will....
Does that ever bring back memories!!!  I did it with a Silver 92, 10 speed, attached to the gasoline tanker behind me.  Stupid speed bump >:D !!

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #35 –
I really don't know what to say or even if this is a good or bad thing but after using a light duty power washer to clean everything up, the transmission works just fine.

There was lots of ice, snow, dirt, and rocks still packed in various crevices on the MH until the power washing but now that everything has been cleaned I'm not having any issues.  I would very much like to know what the issue was and am still a bit concerned about it but I may just have to chalk it up to something being frozen solid. The engine compartment is very susceptible to being packed with snow/ice if driven in deep snow so maybe the lesson to take away here is to avoid it.

Thank you all for your help.

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #36 –
Quote from: rsihnhold –
I really don't know what to say or even if this is a good or bad thing but after using a light duty power washer to clean everything up, the transmission works just fine.

There was lots of ice, snow, dirt, and rocks still packed in various crevices on the MH until the power washing but now that everything has been cleaned I'm not having any issues.  I would very much like to know what the issue was and am still a bit concerned about it but I may just have to chalk it up to something being frozen solid. The engine compartment is very susceptible to being packed with snow/ice if driven in deep snow so maybe the lesson to take away here is to avoid it.

The comment about ice reminds me of an issue Dave Stevens posted about a while back; this one on an SOB but perhaps a similar issue with the connection on the transmission speed sensor?

Check engine light

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #37 –
Where is the location for the speed sensor on the MD 3060 tranny?

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #38 –
Peter,

From memory (not at coach) there are two.  I have replaced the one on the front driver's side of the transmission.  Easy, as it is external to the transmission.  One bolt and disconnect wire connector.

Brett

Re: Allison MD3060 Won't Shift Into Gear- Any Advice Helpful

Reply #39 –
Indeed, we had a problem on the MD3060 on our 37' SOB PB that resulted from driving in blizzard conditions. Ice accumulated on a cable that connected to the bottom of the transmission. The weight of the ice pulled the plug from the transmission. The transmission went to "limp" mode. It operated properly in R, N, 1, and 2. It would not shift beyond 2. The error code indicated loss of speed sensor. I warmed the cable and connectors with a hair dryer. All worked well after I seated the plug properly.

My recollection is that the connection was near the bottom of the transmission somewhere near the output end. It was easy to find while lying on my back under the coach.

After that trip, I looked for a coach that would keep us safe in blizzard conditions in case we made another bonehead decision that put us in harm's way. We've been back to the same area in similar conditions in the Foretravel. We have the capacity to hunker down and wait for better weather.

DON'T DRIVE UNDER HAZARD CONDITIONS unless you are safer driving than you would be stopped!