Community Forums

oldguy70 · 09-03-2019, 03:17 PM

I have trouble getting the trans in gear. Sometimes it goes into gear and
other times it won't. The Allison service tech thinks it is some type of
inhibitor. I have the jacks inhibitor disconnected and a new engine speed
sensor. Does anyone know of any other inhibitor. I have had this problem
for a few years, but the not going into gear really became a problem on this
trip. I have gone the last 2000 miles never knowing if it is going into gear or
not. Also when I first start up the tans won't shift down automatically with
the exhaust brake. After a few miles it will work again. I'm wonders if I
have a bad EUC

twinboat · 09-03-2019, 03:36 PM

It won't go in gear if the idle is to high.

Make sure your engine is idling at the proper speed.

winniman · 09-03-2019, 03:44 PM

My friend was having trouble with his. It turned out there was a wiring harness going to the transmission. It was on top of the tranny. It had another heavy cable laying on it, and had worn partially through about five wires. His tranny would shift intermittently. We found the short by wiggling the wires in the area of transmission. If the tcm loses its ability to communicate, it will not allow the rv to start, the jacks to go down, and many other problems. If the transmission doesn't know what gear it is in, it basically shuts everything down. Check for a worn wire. Could be a similar problem to my friends.

vito.a · 09-03-2019, 04:54 PM

Does it not go into Drive or Reverse?
Will it go into neutral?
What is the idle speed?

oldguy70 · 09-03-2019, 07:33 PM

When it won't go into gear, it won't go into drive or reverse. What seems to work is when
the indicator is flashing is to stop the engine with my finger on the drive button and as
soon as the engine has stopped I put the ignition back on and the indicator will read as
I'm ready to drive. I wait about a minute turn the ignition off and then quickly start
the engine and quickly put it in gear and then it works. We are stopped for the night
and we will be home tomorrow. I will check the wiring when I get home. Changing engine speed doesn't make any difference.

oldguy70 · 09-04-2019, 05:47 PM

I got home today and no trouble getting into gear today. Same trouble with the down
shifting when the exhaust brake is applied. It took 5 miles before it would work.

robisinwa · 09-09-2019, 09:16 AM

I have a '03 Dynasty. Couple years ago, wouldn't go into any gear... was a relay back in the engine compartment, I forget what the lockout was for, not the slides but something the system didn't think was right... swapped the relay with one not in use at the time, transmission worked until I got a new relay to put back in its place.

Just a thought.

oldguy70 · 09-09-2019, 11:43 AM

Thanks Rob, I will look at all the relays in the electrical compartment. Allison tech thinks
there is lockout some where and that will give me another place to look. I don't think
there is any lockouts for the steps.

robisinwa · 09-09-2019, 10:57 PM

Here you go.. left side of the engine while looking at the engine... remove the the square cover, bank of relays in there, you can tell the one I replaced easily. What it doesn't have is a label any longer; I saved the old relay to pull the sticker off but dang if I can find it at the moment.

<OPPS>
Having just posted this the first time, I realize I may have miss led you... the relay I replaced was for a transmission in neutral for the engine to turn over and start, not a transmission shift into gear issue. There are more "if, and, or's" built into these rigs, I forget which issue I have dealt with or dealing with at times.

I know I have had the won't go into gear issue before as well, but this issue with the relay was specifically to get the engine to turn over (which it wouldn't) till I swapped the relay with the air conditioner relay to get it to start.

I'll keep pondering for ya!