tranmission vibration when shifting

I have a 93' suburban,4WD, 5.7L. When it shifts into OD at around 60mph, I get a sever vibration. This also occurs when towing at lower speeds, but usually around this speed. I doesnt last long, just a few seconds. I can feel the vibration when going into OD or shifting down.

I have a 93' suburban,4WD, 5.7L. When it shifts into OD at around 60mph, I get a sever vibration. This also occurs when towing at lower speeds, but usually around this speed. I doesnt last long, just a few seconds. I can feel the vibration when going into OD or shifting down.

Welcome to your first post on AF
Try unpluging tour TCC solenoid and see if it is in the lockup clutch.
If so change trans fluid and filter and try a bottle of Lube-Gard red bottle.
MT

check your center support bearing in the center of the drive shaft. Also look at the U-joints. the u-joints can cause vibration when accelerating and the support bearing can cause vibrations when the torque changes. Those would be my first checks.