allison converter lockout malifuction

[av8or]

I have a M923a2 in which the converter will not release. The lockout is not releasing at low rpms. Any suggestions??

 

[Suprman]

Drain the fluid and drop the pan and look at the filter see if there is metal shavings and how the fluid looks and go from there. Other than that take it to an Allison dealer and see what they say.

 

[av8or]

Drain the fluid and drop the pan and look at the filter see if there is metal shavings and how the fluid looks and go from there. Other than that take it to an Allison dealer and see what they say.

No metal, new fluid & new filter, twice on oil and external filter no joy.

 

[quickfarms]

The piston can crack. Unfortunately you basically have to tear the transmission apart to change it.

 

[av8or]

The piston can crack. Unfortunately you basically have to tear the transmission apart to change it.

Thanks, That's a last resort. just hoping for a magic fix.

 

[quickfarms]

Thanks, That's a last resort. just hoping for a magic fix.

Take it to an Allison service center and let them diagnose it.

There is a bunch of adjustments that can affect the lock up.

Does it stay locked all the time or is this just an issue in certain gears, rpm or speed.

When you serviced it did you drop the pan and replace the internal filter. If you replaced the internal filter did you make sure the pickup tube was the correct length?

 

[av8or]

Take it to an Allison service center and let them diagnose it.

There is a bunch of adjustments that can affect the lock up.

Does it stay locked all the time or is this just an issue in certain gears, rpm or sp

When you serviced it did you drop the pan and replace the internal filter. If you replaced the internal filter did you make sure the pickup tube was the correct length?

It stays locked all the time and has sense I got it from Warner Robins (was a supply truck. Yes pick up tube is OK