CLASS RACER FORUM - View Single Post - GM 4l80e trans vibration in O/D when towing

rognelson777 · 02-02-2013, 01:55 PM

Towing with a 1998 motorhome, has 7.4l chevy towing a 28ft champion trailer. When cruising at 65 mph on flat ground all is well, as soon as we hit grade, vibration starts, feels like the converter cannot decide to unlock or trans wants to downshift. If I depress gas pedal to full throttle it will downshift and vibration stops, then it seams to upshift but not lock up converter, when back to level ground converter locks up and all is well. no other trans issues. Motorhome has 58,000 miles.

Been researching options, 1 is to upgrade converter to TCI/hughes/B&M
2 is to rebuild trans.
3 Fast has a tuner / transmission re calibration programmer that will change transmission settings.

also thinking off upgrading exhaust for a little more horsepower and torque.

If all of the above is necessary, then may be time to upgrade motorhome to newer model or diesel.
Any recommendations ?

02-02-2013, 01:55 PM	#1
rognelson777 Member Join Date: Dec 2010 Posts: 376 Likes: 20 Liked 135 Times in 74 Posts	GM 4l80e trans vibration in O/D when towing Towing with a 1998 motorhome, has 7.4l chevy towing a 28ft champion trailer. When cruising at 65 mph on flat ground all is well, as soon as we hit grade, vibration starts, feels like the converter cannot decide to unlock or trans wants to downshift. If I depress gas pedal to full throttle it will downshift and vibration stops, then it seams to upshift but not lock up converter, when back to level ground converter locks up and all is well. no other trans issues. Motorhome has 58,000 miles. Been researching options, 1 is to upgrade converter to TCI/hughes/B&M 2 is to rebuild trans. 3 Fast has a tuner / transmission re calibration programmer that will change transmission settings. also thinking off upgrading exhaust for a little more horsepower and torque. If all of the above is necessary, then may be time to upgrade motorhome to newer model or diesel. Any recommendations ?