Mod - adding downshift from overdrive

[x0duke0x]

So I don't know about this, but here goes.
I want to have the ability to press a button and allow my 4.2l transmission to downshift out of overdrive and into the gear between overdrive and 3rd gear....
The button I wanna use is from the TBSS AWD gear ahift assembly. It's the button for traction control. I want to use this button.

So first I'm sure a simple button can give out a on/off signal.
Seconday... Can we somehow program or wire up the transmission to do so?? Thanks in advance.

 

[The_Roadie]

There is no gear between 3 and 4th. There is a TCC (torque converter clutch) that locks up and might make you THINK there's another gear past 4th as the RPM goes down. But there's a good and valid reason for the existence of the TCC. Why would you want to defeat it?

 

[x0duke0x]

Ok.... Yah again I don't know crap about my transmission. Ill look into the TCC stuff. I thought the feeling of a downshift was it going into a drive gear. So that helps me out a bit more.

 

[x0duke0x]

Thank you again all mighty roadie.

 

[IllogicTC]

Since the last "gear" (the lockup of the TCC) is electronic, it may not be too hard to defeat it, but it may throw a check engine light unless the CEL for it is tuned out.

 

[Sparky]

Not sure why you want to defeat the TCC lockup? Just leads to poor mpg and elevated transmission temperatures. What's the goal you're trying to achieve?

 

[x0duke0x]

Well... It really to get some insight on this mod, but it really isn't necessary if it means that there are more cons then pros. But this is a good talk, I never knew what a TCC was until this post. So yah, I just wanted to downshift instead of shifting down into the 3rd gear.l, again I know why it's there, so I'm sure I won't wanna change it up. Thanks guys!

 

[Sir ffeJ]

Perhaps you would benefit from a tune from PCMofNC.
They can adjust the shifts of our vehicles.

 

[limequat]

Yah...TCC lockup points can be tuned for all four (and only 4) gears.

 

[IllogicTC]

Yah...TCC lockup points can be tuned for all four (and only 4) gears.

There is also a transmission mod where you replace the PWM TCC solenoid in the transmission with a different one, apparently instead of just gliding into lockup it has a definite feel to it (does Torque Management have something to do with this too?), almost like you're hitting 5th gear except of course you're not.

 

[shotorye]

To the OP (and a nod to IllogicTC) I've also wondered this same thing. It would be nice for the transmission to be able to lock down into lower RPMs while in 4th gear on the highway - obviously gaining better fuel mileage. I'm on the fence on whether or not to go PCM4Less or not - there are definite gains but the almighty $ may not be worth it.
Illogic TC - I've seen a Youtube video where the solenoids in the lower part of the tranny are physically switched out. Are you saying there is a way to replace/modify the appropriate solenoid to allow for a lockup to occur sooner? Honestly, I regularly have to accelerate or decelerate in order to find the magic move to engage 4th gear to drop to a lower RPM.
I'd appreciate either more explanation on this or a link to where I can find it if anyone can provide it!

 

[HARDTRAILZ]

Hope you dont stay out of lock up too long or you get to watch your transmission temps skyrocket.

 

[Mounce]

To the OP (and a nod to IllogicTC) I've also wondered this same thing. It would be nice for the transmission to be able to lock down into lower RPMs while in 4th gear on the highway - obviously gaining better fuel mileage.

It already does that, it drops RPM's as low as it can via locking the torque converter. The OP was wanting to manipulate this function.

 

[Blckshdw]

I'm on the fence on whether or not to go PCMofNC or not - there are definite gains but the almighty $ may not be worth it.

You may, or may not, see returns financially (MPGs) from getting tuned, but you damn sure will enjoy driving your truck a lot more.

 

[x0duke0x]

Yah I got my PCM tune from NC 2 days ago, today I'll be taking it on a 5hr road trip. So I'll let you know, but I was driving in 14-15MPG before the tune and I'm getting a stong 16-17MPG but that's only based on 2 days after I floored the petal a few times, good this new time is great..