Allision Transmission Help

[savarese1]

So they finished the install for the port transmission. We have reverse but no forward.

 

[SeaWhisper]

Was the shifter rod centered when they placed the shift arm on the splines. Just a thought.

 

[MikeP]

Sounds like "They" didn't do the work properly...they certainly didn't check anything. Can you contact them and have them come back out or are the installers just heavy-lift goons as opposed to mechanics?


Was the Hydreco transmission pump rebuilt at the same time? If the pressure is low, the tranny can have reverse but not forward; also, is the transmission oil at the proper level?

Also, when you say there is no forward, have you tried placing the lever in forward and leaving it there for up to 10 seconds to see what happens as opposed to just shifting and, after a second or two moving it back to neutral? Per Arcadia (Allison tranny "experts") it is not unusual for some of these trannies to require "a bit of time" to engage forward, if they haven't been run for a while. Then, subsequent shifts are normal.

So if you haven't, put it in forward and leave it there for 10 seconds and see what happens. If it engages, it will probably shift "normally" from then on if it sees regular use. Then, when it sits unused for another month or whatever, it may do the same thing again initially but return to normal again until the period of non-use where the same thing may occur.

 

[saltshaker]

Have them figure it out but I would be looking at oil level, pressure and linkage. As Mike said see if you truly have no forward or is it just a long delay. If it is a delay and doen't improve after the first 2-3 shifts or when the gear is warmed for the first time, I'd be looking at the Hydreco pump to see if the pressure is set right and/or does it need a rebuild.

 

[savarese1]

Thanks everyone. They think they have a seal that is backwards causing a low pressure issue. Now they have to disconnect the tranny which means pulling everything out of the salon again and pulling in the hoist to lift the trans and see what is going on. JEEZ>>>...
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[34Hatt]

Thanks everyone. They think they have a seal that is backwards causing a low pressure issue. Now they have to disconnect the tranny which means pulling everything out of the salon again and pulling in the hoist to lift the trans and see what is going on. JEEZ>>>...
.

Guess it wasn't done in a real transmission shop?

The shop I use can bench test one tell you the shift times and pressure's and they run them for hrs to make sure there is no leaks.