Allison 6sp: LBZ Shift Range Inhibited

Ne-max

I like turtles
Nov 15, 2011
3,361
64
48
Lincoln, Ne
Having a issue with a customers trans I built a couple years ago using Evan's kit. When it gets to around 150 degrees it will give me the shift range inhibited on the dash. If I put it in neutral and go back to reverse it will go with a slight delay.
Works perfect cold.
No codes
Was trans fluid in connector. Replaced seal and cleaned.
Fluid is bright red.
Shifts and works great in forward gears.
Adjusted cable.
Any ideas?
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,686
232
63
Fullerton CA
Check the solenoids

Nothing to do with it.
Shift range inhibited means there was no gear train pull down. What tha means is; Input shaft must stop turning before a TCM commands a gear change. A clutch did not apply to make this happen. Could be a stator body problem or a worn out clutch. Inspection of the sump filter may tell you something.
 

Ne-max

I like turtles
Nov 15, 2011
3,361
64
48
Lincoln, Ne
Not really. Tossed in my spare valve body and it fixed the issue. If I had more time I would had tried valves.