no overdirive 4l60e
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no overdirive 4l60e
the transmission was rebuilt about a year ago and about 3 weeks ago i put a shift kit and 3600rpm fuddle torque converter in. idk if that would have anything to do with it but tonight i was cruising about 70 and it just fell out of overdrive and went into third. all other gears are fine. what could have caused this? does the trans already need rebuilt again?
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I'd suspect the TCC going unlocked, possibly from an
immature slip code (P1870?). Though maybe LT1s act
different / have different codes. If the converter can't
hold then it quits trying until you make it better. This
would go back to trying again, on next key-on until
the slip threshold is violated again; 3 in a row and it'll
set the light. At least on the LS1 setups.
immature slip code (P1870?). Though maybe LT1s act
different / have different codes. If the converter can't
hold then it quits trying until you make it better. This
would go back to trying again, on next key-on until
the slip threshold is violated again; 3 in a row and it'll
set the light. At least on the LS1 setups.
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the car is down for a head swap so it will be about a month before it is up and running again anyway. but i will need to get the car retuned for the heads so what should i tell my tuner to do? just make it where the converter never tries to lock up or what?
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Full TCC PWM duty cycle at all times
Reduce low-commanded-line force motor current
to get more line at light cruise; this is something
I spent a lot of time road-logging to get right, and
suspect the LT1 may be differently set up. I have
posted some Excel 'sheets with good trans settings
(for low-mods LS1) before, don't have that on this
computer but should be either in this or PCM forums
that you can turn up in search, maybe your guy
can find some useful stuff in it.
Raise allowed-TCC-slip-RPM to set slip codes.
Disable any "slip learning" which keeps TCC on the
edge of "too much" if active.
Reduce low-commanded-line force motor current
to get more line at light cruise; this is something
I spent a lot of time road-logging to get right, and
suspect the LT1 may be differently set up. I have
posted some Excel 'sheets with good trans settings
(for low-mods LS1) before, don't have that on this
computer but should be either in this or PCM forums
that you can turn up in search, maybe your guy
can find some useful stuff in it.
Raise allowed-TCC-slip-RPM to set slip codes.
Disable any "slip learning" which keeps TCC on the
edge of "too much" if active.
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Full TCC PWM duty cycle at all times
Reduce low-commanded-line force motor current
to get more line at light cruise; this is something
I spent a lot of time road-logging to get right, and
suspect the LT1 may be differently set up. I have
posted some Excel 'sheets with good trans settings
(for low-mods LS1) before, don't have that on this
computer but should be either in this or PCM forums
that you can turn up in search, maybe your guy
can find some useful stuff in it.
Raise allowed-TCC-slip-RPM to set slip codes.
Disable any "slip learning" which keeps TCC on the
edge of "too much" if active.
Reduce low-commanded-line force motor current
to get more line at light cruise; this is something
I spent a lot of time road-logging to get right, and
suspect the LT1 may be differently set up. I have
posted some Excel 'sheets with good trans settings
(for low-mods LS1) before, don't have that on this
computer but should be either in this or PCM forums
that you can turn up in search, maybe your guy
can find some useful stuff in it.
Raise allowed-TCC-slip-RPM to set slip codes.
Disable any "slip learning" which keeps TCC on the
edge of "too much" if active.