4l60e tunerpro rt and torque signal pressure doesn't exceed 127

[pima.1971]

0D 7247 in 94 k1500.
Just rebuilt the tranny and it showed thee was a poblem as i was getting clutch material in the pan. A lot of it. So did a pressure gauge test before tear int down. I determined it was low line pressure. Now in limp mode it makes 240psi. Assuming it was rebuilt right, i notice with a gauge on it again the pressure is higher but not rising past 130psi at aggressive throttle. Data logging show the torque signal pressure never goes above 127 which seems to correlate to the pressure gauge. In tprt I tried to change the PE line pressure vs input speed. It will not go over 127. I put 200 and save it. It comes back as 127. What gives? Any other tuning suggestions to change line pressure as load inceases?

TIA
Pima.1971

[RobertISaar]

IIRC, it is code-limited to 127, but i forget why.

[pima.1971]

IIRC, it is code-limited to 127, but i forget why.


So how would one raise the line pressure to the 225psi for wot?

[RobertISaar]

i don't think it is possible. maximum line pressure is achieved with no current going to the pressure control solenoid, if you're seeing little to no commanded current, the PCM isn't capable of raising line pressure further.

from what i understand, the PSI modifiers in the calibration aren't exactly real-world values. they're either an offset to real-world results or they're just scaled for easy reference.

[pima.1971]

Then my new tranny is destined for 3-4 clutch failure? Surely there is some way to get line pressure to raise to match the load. It's a 4wd truck for crying out loud, heavy heavy heavy.

[Fast355]

0D 7247 in 94 k1500.
Just rebuilt the tranny and it showed thee was a poblem as i was getting clutch material in the pan. A lot of it. So did a pressure gauge test before tear int down. I determined it was low line pressure. Now in limp mode it makes 240psi. Assuming it was rebuilt right, i notice with a gauge on it again the pressure is higher but not rising past 130psi at aggressive throttle. Data logging show the torque signal pressure never goes above 127 which seems to correlate to the pressure gauge. In tprt I tried to change the PE line pressure vs input speed. It will not go over 127. I put 200 and save it. It comes back as 127. What gives? Any other tuning suggestions to change line pressure as load inceases?

TIA
Pima.1971

So you have 240 psi with the 12 wire connector unplugged? That tells me your pump and pressure regulator is working right. Your EPC also seems to be working correctly as well. I would have to look at the $0D hack and code to see what I can find, but worse case you might measure the resistance of the EPC solenoid and then add some resistance to the circuit to limit the current to the EPC, increasing line pressure across the board. You can actually go about this two different ways. You can make a variable pressure rise by adding resistance parallel to the ECP to chassis ground or you can offset the pressure by adding resistance in series with the EPC. With a petentiometer and a resistor you could even make this adjustable. With two potentiometers you could add resistance both in series with and parallel with the EPC allowing you to adjust pressure at both WOT and part-throttle.

Very few 4L60E tunes use much line pressure once the truck is rolling, regardless of TPS% What value do you have in your Line Pressure Tables. I usually use 90 across the board above 50% TPS and sometimes as much as 90 by 30% TPS.

On the otherhand, this solution works well too.

http://www.ebay.com/itm/TRANSGO-4L60E-46-MOD-Vacuum-Modulator-Kit-Replaces-EPC-/260134015181#ht_1963wt_1124

[pima.1971]

The bin was originally made by 93v8s10.

Also recently downloaded the adx "a218 trans1 $OD TP5 V250" and that is where I discovered the "current torque signal pressure" not rising above 127

[pima.1971]

Is there another mask/bin combo that would allow this change that would work with my ecm. I will be travelling shortly and won't be able to replay for 90 minutes to 2hrs. Thanks for your guy's help tying to get this resolved. Fresh trans doesn't have 5 miles on it yet.

[Roadknee]

Do you have any information, or a link to how 93V8S10 developed that transtune bin? It's completely different than any factory bin, and I'm interested in the thought behind the changes. Thanks

[pima.1971]

No idea.

[EagleMark]

I don't know what happened to 93V8S10 ? But he just vanished awhile ago, does anyone know him personally?

$0E, $31 and $E6 should all run in your $0D PCM if you wanted to try... I'm no help to the trans PSI though... Don't think GM would lock it to 127 on one and not anohter mask being it would be same trans.