Automatic overdrive control

Carl · 04-05-2008, 05:40 PM

Just thought about this idea so thought I'd share it for any feedback.

I always turn my OD off under 45mph. It'd be cool if you started the truck with OD off, then when you reached a certain speed it would give the ground pulse to the pcm activating OD. Once you dropped below a certain speed, it'd give another ground pulse deactivating OD.

What do you think?

__________________
1994 Dodge Ram 2500 4X4 Auto RC/LB

Joe G. · 04-05-2008, 07:59 PM

Actually, that's the way the stock setup works. If you want to have better control over when those events occur, then you have to do some modifications. There is a long thread on another web site that goes into all that in detail.

__________________
KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.

Carl · 04-05-2008, 09:31 PM

What kind of modifications? I'm kinda interested in it. I mean if the stock setup works like that, why do I have to push my OD off button at low speeds?

__________________
1994 Dodge Ram 2500 4X4 Auto RC/LB

Joe G. · 04-05-2008, 09:38 PM

The basic control is the TPS. The stock setting allows OD at a pretty low speed. The idea being to increase MPG. More throttle raises the speed at which the shift to OD happens or the downshift from OD happens. The details and a discussion of various ways to deal with it are here: TPS myth buster - TDR Roundtable . However, I don't think non-members can access it since it's a old thread. The basic idea is to replace the TPS with a pot that can be adjusted in the cab. There are some drawbacks and I don't recall all the details.

__________________
KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.

Carl · 04-05-2008, 10:04 PM

Great, thanks Joe, I'll look into it.

__________________
1994 Dodge Ram 2500 4X4 Auto RC/LB

TB1 · 04-06-2008, 10:32 PM

If this is not allowed please remove. The link will show you how to install a relay so the OD is off until you press the switch to activate it. This is one of the first mods I did when I bought my truck.

AT OD switch inverter

Alphawhiskey · 04-10-2008, 09:20 AM

hmmm. I'm consfused or one if you are

not followinw what you want to do. I did the potentiometer of the round table forum. Works great. 0 drawbacks in my opionon. If you want control of when it hits od do the pot thing. If you want lock up control you can do that also. All though it can be very tough on the tc.

__________________
96 2500 4x4 Home gound #100 plate. Gutted AFC, LOVE IT! Silencer ring MIA. KDP killed fell out miles ago but all was ok. Heavy duty TC valve body. BHAF custom 4' intake Silverline 4' . Autometer; pyro, boost, tranny. Lots o lights, custom cargo rack.

Joe G. · 04-10-2008, 12:46 PM

The drawback in some people's opinion is that you loose kick down ability. I'm not sure that is a big deal. It isn't for me. I have not done the mod because my TPS has been working properly. However, it is starting to act up again so I might make that mod.

__________________
KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.

gary1930 · 04-24-2008, 01:32 AM

could you pleae send ths mod t me i have spent 2000.00 tring to fix the way late upshift thanks

Joe G. · 04-24-2008, 01:35 AM

Email me at jgeorge1@suddenlink.net so we can talk about it.

__________________
KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.

04-05-2008, 05:40 PM	#1 (permalink)
Carl Cummins Fan Join Date: May 2006 Location: Lansing, MI Posts: 91 Thanks: 0 Thanked 0 Times in 0 Posts Carl's Truck Pics	Automatic overdrive control Just thought about this idea so thought I'd share it for any feedback. I always turn my OD off under 45mph. It'd be cool if you started the truck with OD off, then when you reached a certain speed it would give the ground pulse to the pcm activating OD. Once you dropped below a certain speed, it'd give another ground pulse deactivating OD. What do you think? __________________ 1994 Dodge Ram 2500 4X4 Auto RC/LB

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04-05-2008, 07:59 PM	#2 (permalink)
Joe G. Diesel Head Join Date: Apr 2007 Location: Eureka, CA Posts: 1,644 Thanks: 2 Thanked 38 Times in 35 Posts Joe G.'s Truck Pics	Actually, that's the way the stock setup works. If you want to have better control over when those events occur, then you have to do some modifications. There is a long thread on another web site that goes into all that in detail. __________________ KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.

04-05-2008, 09:31 PM	#3 (permalink)
Carl Cummins Fan Join Date: May 2006 Location: Lansing, MI Posts: 91 Thanks: 0 Thanked 0 Times in 0 Posts Carl's Truck Pics	What kind of modifications? I'm kinda interested in it. I mean if the stock setup works like that, why do I have to push my OD off button at low speeds? __________________ 1994 Dodge Ram 2500 4X4 Auto RC/LB

04-05-2008, 09:38 PM	#4 (permalink)
Joe G. Diesel Head Join Date: Apr 2007 Location: Eureka, CA Posts: 1,644 Thanks: 2 Thanked 38 Times in 35 Posts Joe G.'s Truck Pics	The basic control is the TPS. The stock setting allows OD at a pretty low speed. The idea being to increase MPG. More throttle raises the speed at which the shift to OD happens or the downshift from OD happens. The details and a discussion of various ways to deal with it are here: TPS myth buster - TDR Roundtable . However, I don't think non-members can access it since it's a old thread. The basic idea is to replace the TPS with a pot that can be adjusted in the cab. There are some drawbacks and I don't recall all the details. __________________ KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.

04-05-2008, 10:04 PM	#5 (permalink)
Carl Cummins Fan Join Date: May 2006 Location: Lansing, MI Posts: 91 Thanks: 0 Thanked 0 Times in 0 Posts Carl's Truck Pics	Great, thanks Joe, I'll look into it. __________________ 1994 Dodge Ram 2500 4X4 Auto RC/LB

04-06-2008, 10:32 PM	#6 (permalink)
TB1 Cummins Fan Join Date: Oct 2006 Location: Saltspring Island BC Posts: 47 Thanks: 0 Thanked 1 Time in 1 Post TB1's Truck Pics	If this is not allowed please remove. The link will show you how to install a relay so the OD is off until you press the switch to activate it. This is one of the first mods I did when I bought my truck. AT OD switch inverter

04-10-2008, 09:20 AM	#7 (permalink)
Alphawhiskey Cummins Fanatic Join Date: Apr 2007 Location: Mn Posts: 136 Thanks: 0 Thanked 0 Times in 0 Posts Alphawhiskey's Truck Pics	hmmm. I'm consfused or one if you are not followinw what you want to do. I did the potentiometer of the round table forum. Works great. 0 drawbacks in my opionon. If you want control of when it hits od do the pot thing. If you want lock up control you can do that also. All though it can be very tough on the tc. __________________ 96 2500 4x4 Home gound #100 plate. Gutted AFC, LOVE IT! Silencer ring MIA. KDP killed fell out miles ago but all was ok. Heavy duty TC valve body. BHAF custom 4' intake Silverline 4' . Autometer; pyro, boost, tranny. Lots o lights, custom cargo rack.

04-10-2008, 12:46 PM	#8 (permalink)
Joe G. Diesel Head Join Date: Apr 2007 Location: Eureka, CA Posts: 1,644 Thanks: 2 Thanked 38 Times in 35 Posts Joe G.'s Truck Pics	The drawback in some people's opinion is that you loose kick down ability. I'm not sure that is a big deal. It isn't for me. I have not done the mod because my TPS has been working properly. However, it is starting to act up again so I might make that mod. __________________ KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.

04-24-2008, 01:32 AM	#9 (permalink)
gary1930 Newbie Join Date: Apr 2008 Posts: 4 Thanks: 0 Thanked 0 Times in 0 Posts gary1930's Truck Pics	could you pleae send ths mod t me i have spent 2000.00 tring to fix the way late upshift thanks

04-24-2008, 01:35 AM	#10 (permalink)
Joe G. Diesel Head Join Date: Apr 2007 Location: Eureka, CA Posts: 1,644 Thanks: 2 Thanked 38 Times in 35 Posts Joe G.'s Truck Pics	Email me at jgeorge1@suddenlink.net so we can talk about it. __________________ KDP tab fix info and fuel system article jgeorge1@suddenlink.net '95 2500 CC auto 4X4, 3.54, EGT, boost, fuel pressure, trans temp guages, PacBrake, TST #5, DTT VB, DTT triple disk TC, DTT billet flex plate, Cummins chrome kit.