I have a friend who has a 2004 LB7 that has the overdrive lockout. I have a 2004.5 LLY with the lockout. Question is, did they use the same transmissions for awhile? I didn't think the LB7's had the lockout.
Thanks, Terry
Thanks, Terry
LB7 & LLY Allison questions
- Thread starter tpitt
- Start date
IIRC, only the 01's were missing the lockout. There is a difference between LLY and LB7 Allisons, the G solenoid is LLY specific. Some of the fluid fittings are different on early Allisons as well.
01-02 didn't have the OD/lo from the factory. 03+ you held the tow/haul in for a few secondes and got OD/LO, or just bump it for tow/haul. 01-02 you have to wire in 3 wires, a momentary switch, and an LED indicator to get OD/LO as well as flashing your TCM to the latest OS available for it. OD/LO is done electronically so the trans itself doesn't make much of a difference. 04+ did have the G solonoid in them(only the LLY's used it though), and mid year 03 they changed the trans cooler fittings.
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All '04 and later Alli's had G solenoid. They were only lit up in the 8.1 and LLY. Trans changed in mid year '04.
Appreciate all the answers. Thank you guys.
Next question. Will the valve body off of a LLY work on this 2004 LB7? The reason I'm asking is I have a valve body with transgo kit installed and he wants one. I converted mine to 6 speed.
Thanks again, Terry
Yes it will. If you don't have a wire for the G solenoid just ignore it as the computer isn't looking for it anyways on the early model.
G solenoid drops mainline pressure in the Alli when throttle position goes below 8%. This is done to help cool the trans while it is at idle. Pressure goes back to normal above 7% throttle position.