E40d altering?

[Andylad13]

i can get the 1/2 shifts to come on when i drive, but they only stay in that range for a split second most of the time. is there anyway i can get them to stay in that 1/2 shift for a little longer?

she shifts as follows: 1,1.5,2,2.5,3,4

 

[JwS]

The 1/2 shifts you are feeling is the TC locking, in the lower gears it will be delayed a little bit, and also more noticable I think. In the higher gears it will lock almost simultaneous with the shift, so you won't really feel it.
JwS

 

[LCAM-01XA]

You can do what Zigg and many others have done so they can control the lockup manually, read up on it here:

http://www.oilburners.net/forums/showthread.php?t=22806

 

[Andylad13]

thanks for the link, but could someone explain how everything works when the TC locks up?? i am very unfarmiliar with automatics.

 

[LCAM-01XA]

Have you ever driven a stick-shift? Well, think about the torque converter as a clutch that always slips a bit - the flywheel is turning at one speed, the tranny input shaft at a slightly slower speed. A regular non-lockup converter does that all the time, whereas a lockup converter will actually lock the turbine wheel inside the converter to the converter housing at some point, thus eliminating the converter slip and the associated power loss. For in-town driving you don't need the lockup feature engaged as you're shifting gears pretty much all the time, but on the freeway it works nice - you can lockup the converter in 3rd gear and have more towing power uphill, or you can use your engine as a brake more effectively on the way down the hill, all cause there ain't no slip in the converter.

Makes some sense? There's much more to a torque converter than that, obviously, but this is as basic as I can describe the lockup action.

 

[Andylad13]

that definatley helps out, i appreciate the explanation!

 

[zigg]

I'm still working on mine. Manual lockup control is just great. I love it. I can't figure out how to take the lockup out of the loop though without the computer going into "limp" mode though. I'm thinking I might try to figure out what the resistance of the lockup solenoid is, and then put a resistor or a small light inline, so the computer still thinks it's locking up the converter even when it is out of the loop. I'll definately report back...

Zigg

 

[MF2003]

Hey why not buy an extra lockup solenoid.

 

[LCAM-01XA]

Zigg, when does your tranny go in limp mode, when you have the lockup circuit open to prevent the solenoid from engaging? What does it do in limp mode, just maxing out the line pressure and making real stiff shifts? Ain't that actually better for city driving?

I'm thinking, if stiff shifts is the only effect of the limp mode, may as well go with that - limp mode and stiff shifts when no lockup, then with the manual there will be no limp mode as whenever the computer decides to lock the converter as tis already locked anyways. Actually, how often does the tranny computer check for limp mode conditions? I mean, once in limp mode, when you manually lock the converter and the computer decides to lock it up as well, if it sees the lockup signal will it go off limp mode? Or it will stay in limp mode until you manually disable it with a scan tool or whatever?

 

[sootman73]

zigg here is a link to a module a guy built to correct the limp mode problem. about 20 bucks to make with just some parts from radioshack. and since yuo have the switch it'll cost less than that.

http://guzzle.rbmicro.com/tclock.html

 

[LCAM-01XA]

Sootman, the way I read that article it seems like he is only able to lock the converter manually, but in-town he's still running the auto-lockup, which is what most us try to avoid.

 

[sootman73]

ya im not sure on how he made his work. i dont ever mind the limp mode shifting. it goes thru all gears, shifts when its supposed to, and puts line pressure to max. sounds like it would make it a lot harder to burn up clutches this way?

 

[Andylad13]

zigg, i printed out the link that came up earlier in the thread about what you did for your switch, and im interested in doing the same thing.

i just need help in identifying exactly what wires to splice into and their location.

 

[trackspeeder]

ya im not sure on how he made his work. i dont ever mind the limp mode shifting. it goes thru all gears, shifts when its supposed to, and puts line pressure to max. sounds like it would make it a lot harder to burn up clutches this way?

It would be harder burn clutches. But it beats the hell out of the gear train.

 

[sootman73]

im kinda thinking that my banks tranny controller might keep the shifts a little softer than normal limp mode would. it does control the pressure valve. the shifts dont bang hard into the next gear. its about where i like it to be actually. they are a little harder when its hot(80mph freeway driving for 3 hours) but it has always done that.