Hello,
I have a 2001 Silverado 2500HD with a 6.0L engine and a 4L80E transmission. I've noticed recently that when I'm cruising along on the hiway and I back off on the throttle briefly for whatever reason, when I come back up on the throttle the torque converter will unlock briefly then re-lock after a couple of seconds. Is this normal? Does the 4L80E use pulse width modulation (PWM) on the torque converter similar to the 4L60E?
I have become a little bit familiar with issues on the 4L60E and just finished installing a PWM eliminator valve on my Trailblazer with excellent results. I wish I had done it a long time ago. On my Trailblazer the torque converter had gotten very sloppy and was falling out of lock at lower rpms (the torque converter shudder). The PWM eliminator valve and drilling out the separator plate has made the the converter lockup nice and solid again. I am wondering if the same mods are possible on the 4L80E. If the torque converter is not supposed to be releasing I don't want to wait until it gets bad before doing something about it. This trans is otherwise rock solid. I become more sensitive to shifting issues after dealing with the issues I've had on the Trailblazer, so I don't know if it has always had this quirk or if it is something new.
I have a 2001 Silverado 2500HD with a 6.0L engine and a 4L80E transmission. I've noticed recently that when I'm cruising along on the hiway and I back off on the throttle briefly for whatever reason, when I come back up on the throttle the torque converter will unlock briefly then re-lock after a couple of seconds. Is this normal? Does the 4L80E use pulse width modulation (PWM) on the torque converter similar to the 4L60E?
I have become a little bit familiar with issues on the 4L60E and just finished installing a PWM eliminator valve on my Trailblazer with excellent results. I wish I had done it a long time ago. On my Trailblazer the torque converter had gotten very sloppy and was falling out of lock at lower rpms (the torque converter shudder). The PWM eliminator valve and drilling out the separator plate has made the the converter lockup nice and solid again. I am wondering if the same mods are possible on the 4L80E. If the torque converter is not supposed to be releasing I don't want to wait until it gets bad before doing something about it. This trans is otherwise rock solid. I become more sensitive to shifting issues after dealing with the issues I've had on the Trailblazer, so I don't know if it has always had this quirk or if it is something new.