I have a 208 T-Case and 700R4 and 6'' lift. When my truck is under a light load and I am light on the gas (cruising at 15mph in sand with 5psi in tires) it will make a noise like a bad u-joint in the driveshaft as it shifts from 2nd to 3rd gear. It sounds like it is coming from the T-case. I have the stock rear shaft and will be upgrading to a c/v soon, but all of the u-joints are good. I will eliminate the transmission as a possibility because it was factory new 40k ago and has a warranty still. Could this noise be the splines on the slip yoke wearing out and slapping around? Also when I accelerate hard on pavement, I sometimes hear what sounds like forgetting to push in the clutch while shifting with a manual. My rear axle is all new so it isn't the ring and pinion. The output shaft on the t-case looks good, but I don't know how to tell how tight the splines should be from the shaft to the slipyoke. PLEASE HELP!