Overdrive Off is tran still in lockup(tow/haul)?

[RFraser]

When you shut off overdrive I assume that the transmission is still in lock up as in tow/haul except without the OD. I only have dialup here in the back woods,searching takes forever. Appreciate any help. Thanks Rob.

 

[nps]

You are correct. Also, if you are in tow/haul and you drop the gear shift from drive to 2, it transmission will lock the TC in 2nd gear. Found this out pulling my 5er up a big hill while watching the transmission temps climb.



Finally, if you have a jake brake and turn it on, it automatically turns on tow/haul mode without having to hit the button. After the engine warms up, the jake brake will not stay on at a stop light.



I leave my Jake on all the time so I don't have to hit tow/haul or look at the dash light, unless my wife is riding with me. Then I turn it off because she doesn't like the firm shifts I get with my Goerends VB and TC.

 

[RFraser]

Thanks for the reply,great help.

 

[DrDiesel]

OverDrive is the TCC locked. When you activate the the O/D switch this turns the TCC lockup off. The trans is in 4th gear if your moving fast enough.

The TCC control has no bearing on what gear your in when you activate it. It only stops the TCC from coming on.

Lockup is not a gear. It`s the clutch in the T/C and can be commanded on and off. The new 06 48RE has the ability to use the TCC in 2nd, 3rd and 4th gears. The older versions only had TCC in 4th. So remember, when you talk about lockup. It`s not a gear.

 

[GWJCTD]

On my 05 i will hit th button and it revs up (drops a gear) which is great then all of a sudden i will be crusing the it will go back into od just like i hit the button,why? Then i hit the button again then again to get the rpm back up. Stupid to me. i think when i want it off it should stay off,whats the point.

 

[DrDiesel]

On my 05 i will hit th button and it revs up (drops a gear) which is great then all of a sudden i will be crusing the it will go back into od just like i hit the button,why? Then i hit the button again then again to get the rpm back up. Stupid to me. i think when i want it off it should stay off,whats the point.

I don`t think the 05 has o/d lockout, does it... Something was change in the 06 model year. We have both tow/haul and o/d off.

If it`s tow/haul mode only, it rests the line pressure and shift points. It also turns the T/C clutch off and the PCM will re-activate the T/C after it sorts out the correct algorithms, speed, map, tps, rpm, and current gear.

 

[DPKetchum]

05 has NO O/D off.

 

[GWJCTD]

I never said i had an od button,just a t/h button and i was just wondering why when i hit it the rpms go higher and my egts go down like normal and when im pulling this is what i want,to stay like this,but then it will auto kick back and rpms will drop(just like i hit the button again,makes me mad. or i have to stomp on it so it will come back on,such a pain while towing.