Allison will not go in gear

[Tedtoo]

Posting for a friend-she is at a rally that is ending. Original problem was MH would start, but not stay running. Because she had previous problems she disconnected something on engine, then MH would start and run. Seems to go into reverse and move (she cannot back up where she is parked) but when put in drive will not move forward. She has re-connected part she had disconnected. 1996 Monoco Dynasty. I suggested check to see air brake was off, recycle jacks, and check transmission fluid. Coach is running now, but does not move. Any more suggestions? She is 14 miles from nearest small town. Thanks for any help you can offer.

TedToo

[Busskipper]

IMHO - when I think about what has been given as to info - 1996 - little use - User really is not too Mechanically inclined - Algae in Fuel - not going to stop it but indicates very little use - Think that there could be Many, Many different contributing Factors. including - Low voltage and an ECU can do strange things.

Doubt if we'll ever really learn the issue.

JMHO,

[gutfelt]

as said IF the motor starts and runs and goes into reverse as OP clearly defines that it does there is no reason to look at voltages as obviously there fine

[Jim]

Checking battery voltage is always good practice. If possible, when under load when performing the test at hand. Even though in this case, the engine is running when owner is attempting to shift into drive, and it's likely there would be other symptoms if the alternator wasn't doing it's job, it's still good practice.

BTW, you can now buy a digital meter with Bluetooth! With the meter and the app on your phone, it's easy to read voltages when you can't do it alone. Pretty cool way to read meter readings remotely when you don't have a friend handy.

[Farmboy666]

Corkey05 wrote:

gutfelt wrote:

Corkey05 wrote:
The Allison transmission defaults to neutral at 11 volts. It could be in the charging system, and a low battery. A quick jumper from the house batteries (if at full charge) to chassis batteries, would discount that issue.

Not Low voltage at all as OP says it goes into reverse

as two others have said sounds like the rear Brakes are stuck on
I have had that happen

Maybe the OP said it goes into reverse, but the thread title is "Allison will not go in gear". The post is confusing to begin with, but voltage is often overlooked so I mentioned it ... no need to discount any possibility.

Can't include all the details in the title, that's why you read the thread. Low voltage is being discounted because it goes in gear, that's how you eliminate things and get to the problem.

[firemech]

speed sensor has 2 front of trans and rear

[wolfe10]

DSDP Don wrote:
Algae won't stop trans from shifting, but the things she's been unplugging and plugging back in could have changed the idle. If the coach is idling faster than spec, (should be around 700 rpm) the Allison will not shift into gear.

Correct. If idle speed too high, the Allison shift pad will just blink.

But, would do the same for either R or D.

[ArchHoagland]

Keep us posted.

[DSDP_Don]

Algae won't stop trans from shifting, but the things she's been unplugging and plugging back in could have changed the idle. If the coach is idling faster than spec, (should be around 700 rpm) the Allison will not shift into gear.

[Tedtoo]

Update--mechanic came out, fuel filters have algae in them. So, they are changing filters and putting some additive in to kill algae. Will let you know how it goes.

[gutfelt]

Corkey05 wrote:

gutfelt wrote:

Corkey05 wrote:

gutfelt wrote:

Corkey05 wrote:
The Allison transmission defaults to neutral at 11 volts. It could be in the charging system, and a low battery. A quick jumper from the house batteries (if at full charge) to chassis batteries, would discount that issue.

Not Low voltage at all as OP says it goes into reverse

as two others have said sounds like the rear Brakes are stuck on
I have had that happen

Maybe the OP said it goes into reverse, but the thread title is "Allison will not go in gear". The post is confusing to begin with, but voltage is often overlooked so I mentioned it ... no need to discount any possibility.

BUT as said it goes into reverse so obviously it has 12V power so why bother? that's my point

Seems to go into reverse and move

I see your point, but you fail to see mine. I simply offered something often overlooked. If you read the followup they are now claiming it's engine oil. Like I said the post is confusing so why limit idea's? Why do you insist on arguing? They asked for help, so why do you think yours is the only answer?

LOL arguing iam not;; your right I don't see your point:

[Corkey05]

gutfelt wrote:

Corkey05 wrote:

gutfelt wrote:

Corkey05 wrote:
The Allison transmission defaults to neutral at 11 volts. It could be in the charging system, and a low battery. A quick jumper from the house batteries (if at full charge) to chassis batteries, would discount that issue.

Not Low voltage at all as OP says it goes into reverse

as two others have said sounds like the rear Brakes are stuck on
I have had that happen

Maybe the OP said it goes into reverse, but the thread title is "Allison will not go in gear". The post is confusing to begin with, but voltage is often overlooked so I mentioned it ... no need to discount any possibility.

BUT as said it goes into reverse so obviously it has 12V power so why bother? that's my point

Seems to go into reverse and move

I see your point, but you fail to see mine. I simply offered something often overlooked. If you read the followup they are now claiming it's engine oil. Like I said the post is confusing so why limit idea's? Why do you insist on arguing? They asked for help, so why do you think yours is the only answer?

[gutfelt]

Corkey05 wrote:

gutfelt wrote:

Corkey05 wrote:
The Allison transmission defaults to neutral at 11 volts. It could be in the charging system, and a low battery. A quick jumper from the house batteries (if at full charge) to chassis batteries, would discount that issue.

Not Low voltage at all as OP says it goes into reverse

as two others have said sounds like the rear Brakes are stuck on
I have had that happen

Maybe the OP said it goes into reverse, but the thread title is "Allison will not go in gear". The post is confusing to begin with, but voltage is often overlooked so I mentioned it ... no need to discount any possibility.

BUT as said it goes into reverse so obviously it has 12V power so why bother? that's my point

Seems to go into reverse and move

[Corkey05]

gutfelt wrote:

Corkey05 wrote:
The Allison transmission defaults to neutral at 11 volts. It could be in the charging system, and a low battery. A quick jumper from the house batteries (if at full charge) to chassis batteries, would discount that issue.

Not Low voltage at all as OP says it goes into reverse

as two others have said sounds like the rear Brakes are stuck on
I have had that happen

Maybe the OP said it goes into reverse, but the thread title is "Allison will not go in gear". The post is confusing to begin with, but voltage is often overlooked so I mentioned it ... no need to discount any possibility.

[fcooper]

Assuming that the motorhome has an allison transmission, I suggest going through the diagnostic codes provided by the transmission shift selector

The allison 3000/4000 operators manual can be downloaded from the link below.

allison operator's manual

Fred