I'm have some vibration problems with a 71 E body. A hemi was installed in place of the original 383 using Schumacher mounts. Still has the original K member using Schumacher mounts. Replaced the trans mount with the original material sytle, had the drive shaft checked and balanced. Tryed two complete sets of tires and wheels. Still having a vibration while driving at lower speeds untill around 70 mph. Vibration is not as bad but still noticable. I'm wondering if there might be a issue with the engine mounts. Has anyone had vibration problems like this ?