Chackerman
OBS Enthusiast
I have been chasing a hard shifting problem in my 4l80e for awhile now. It’s in a 2000 suburban 2500 6.0l.
Started last summer pulling the travel trailer. Halfway to destination started shifting hard up and down in all gears. Could stop and restart and all would be good for 10-15 minutes then it would happen again. Fluid looked ok, and drove ok otherwise so I made it home and dropped the pan to drain the fluid. Checked codes and no codes.
Fluid looked good and filter was clean. So I proceeded to change the fluid and filter anyways and flush 1litre out and 1litre in at a time through the cooler line and dipstick until new fluid came through the cooler.
Changing oil, filter, and flush didn’t change the problem. Hard shifting usually starts 20 minutes to half an hour into a drivez Shorter drives are no problem and shifts perfect. Tranny and engine temps are normal.
Checked the pass through connector pins and outer harness and all look good, except some transmission oil in the connector(very small amount 1 drop maybe) the pressure control solenoid through the pass through connector and got 4.2 ohms, spec is 3-5 ohms.
Starting to wonder what else it could be. Oil is still clean since the last change, and problem is the same with no other problems after 10,000 more KM. Has anyone had a similar problem for is able to offer some suggestions?
Thanks!
Started last summer pulling the travel trailer. Halfway to destination started shifting hard up and down in all gears. Could stop and restart and all would be good for 10-15 minutes then it would happen again. Fluid looked ok, and drove ok otherwise so I made it home and dropped the pan to drain the fluid. Checked codes and no codes.
Fluid looked good and filter was clean. So I proceeded to change the fluid and filter anyways and flush 1litre out and 1litre in at a time through the cooler line and dipstick until new fluid came through the cooler.
Changing oil, filter, and flush didn’t change the problem. Hard shifting usually starts 20 minutes to half an hour into a drivez Shorter drives are no problem and shifts perfect. Tranny and engine temps are normal.
Checked the pass through connector pins and outer harness and all look good, except some transmission oil in the connector(very small amount 1 drop maybe) the pressure control solenoid through the pass through connector and got 4.2 ohms, spec is 3-5 ohms.
Starting to wonder what else it could be. Oil is still clean since the last change, and problem is the same with no other problems after 10,000 more KM. Has anyone had a similar problem for is able to offer some suggestions?
Thanks!
