Full Line Pressure

[The devil]

Hi to all,
I have a problem with my transmission on G8 it use full line pressure all the time, I have a code ( something wrong with the input speed sensor and it is illuminating the check engine lamp) I went to shop and they say nothing wrong with the trany the problems is from the ECU which I have change it but no luck.
The trany has transgo shift kit installed.

My question is how can I eliminate this code or how can I prevent the trany from using full line pressure.

I disabled the Max pressure under the invalid torque signal under trans dignos but still no luck.

One last question what would happen if I apply the TCC in the second gear ( is it gonna damage the trany)

[madvette08]

I would get the Input Speed Sensor replaced as it is important from the TCM to determine line pressure, shift timing, TCC slip speed and gear ratio. That is the fail safe if a sensor is faulty max line pressure and no TCC lock up. Not good for the tranny to ignore it!

You can apply the converter in second gear the transmission was designed for it. It all boils down to how GM wanted to set up the calibration based on shift feel. The trucks and vettes lock up the converter in 3rd for drive and 2nd for Manual/Sport mode.

Ian

[bluegoat06]

Madvette, 2-3 weeks ago i had the same question, but instead if 2nd, i asked if i could apply TCC in 3rd. couple of people said no because i could damage the trans. i kept looking at different tunes, Camaros and vettes mainly, with the same trans, and found the factory applies tcc in 3rd and 4th in the vettes, normal and sport, the G8's only apply tcc in 4th for normal and sport. when in TUTD, camaros and vettes apply tcc in 2nd,3rd and 4th, the G8's does it in 3rd and 4th.

Then i found a 6l80e reference, http://www.cadillacfaq.com/stsfaq/ts...-07-30-023.pdf

And it appears the torque converters are all the same in this trans from the factory ? and what changes is the trans fluid pan capacity? with that said, can we use the new camaro TCC apply/release setup in the G8GT's ?, if the factory allows us to apply tcc in 3rd gear while in TUTD, what was the big deal not to do the same in sport mode for example ?

And as you mentioned, i was thinking GM wanted to catter a 4 door sedan with a V8 engine to a different group of people, and the G8 came with the slowest and softest trans settings

[madvette08]

The 6l80E's are the same internaly, the only thing that is different then a corvette v a G8 is the bell housing and Output shaft assembly, which are compatible. The 6l80E in the cadillacs use a 258mm twin disk converter vs a 300mm single disk so they use less transmission fluid.

If you also look at a trucks with a 6l80 they also lockup like the camaros, vette and same 300mm converter. You should be fine since you got 1000 lbs less then them lol and around the same wait as a camaro.

Ian

[bluegoat06]

Madevette, I'm going to test the vette approach applying tcc in 3rd and 4th in sport mode, and i was wonder why even though the vette doesn't apply tcc in 1st and 2nd, the factory uses release for 1st gear, why is that ?, actually i've checked the tune from a 08 Sierra 6.2L, and it does the same, there is commanded release in 1st gear even though there is no apply for 1st or 2nd when in normal mode.