Quote from Tony:
You know Fred, the vibration may have always been there, in the past the low rear end gears probably stopped you from driving fast, now you can and the drive shaft is spinning just as fast as it would befire the OD tanny installation.
Tony I think you hit the nail on the head. Since the speedo stopped working I'm not sure how fast I'm actually going, but easily 75 mph+, when the vibration starts. With the old setup (pre-overdrive) I got the truck up to 80 mph one time and noticed no vibrations. The investigation continues...
-ftyler
