For about the last six months or so my truck started getting this strange vibration starting about 50mph and going away at 56mph. It happens in 4th or 5th only when towing or going uphill.
It also happens if you stand on it go get onto the freeway. I have made a few changes since I first felt this. At first I thought it was bad ujoints. Changed them. The getrag was getting noisy so I changed out to a new nv4500hd. Problem still exists. Getting worse. You can also hear it from the floor. I have checked all of the obvious. New trans mts also. Have checked the rear diff-seems fine. No metal inside. Any Ideas? Anybody else had this problem? Is it normal for t-case to have a little play on the rear output shaft? If you let off the pedal going up hill or down hill you feel nothing.
It also happens if you stand on it go get onto the freeway. I have made a few changes since I first felt this. At first I thought it was bad ujoints. Changed them. The getrag was getting noisy so I changed out to a new nv4500hd. Problem still exists. Getting worse. You can also hear it from the floor. I have checked all of the obvious. New trans mts also. Have checked the rear diff-seems fine. No metal inside. Any Ideas? Anybody else had this problem? Is it normal for t-case to have a little play on the rear output shaft? If you let off the pedal going up hill or down hill you feel nothing.