Blew the axle up at URE last Oct and this week finally got the replacement axle installed as well as made the conversion to a 4 bolt flange from rotoflex. Here's where the problems began. Everything is secure, no play in the driveshaft, fresh diff oil(75w-90). When I accelerate and am on the gas pedal, things seem normal. When I let off the throttle, I begin to get a gear/bearing type noise until it slows to about 25 mph then it goes silent again. I have checked the U-joints on the driveshaft, they seem good. Again no play at the new flange. I'm lost as to what this could be, my only guess is perhaps a wheel bearing or something in the gears.