I've been back down in Texas for school for about a month now. When I was driving home tonight, I noticed a vibration when I let off the accelerator, it was gone when at a constant speed or accelerating. In the short time that I could look at it, it didn't seem to matter if the truck was in gear or not or if the clutch was engaged/disengaged. The vibration is more noticeable at higher speeds. Any ideas for me to check out in the morning?? 
Thanks,
Jake

Thanks,
Jake