Sometimes when I apply the gas lightly, I will feel a significant shudder/shake from the rear end from about 0-3 MPH or so. I can duplicate it when the truck has been recently started, in drive, 1 foot on the brake, and one foot barely on the gas, and modulating the brake to maintain 1-2 MPH while turning. It is a constant shake from the rear end or a shudder. It shakes the whole truck.....not violently, but notably....like running over some rumble strips in the road at lower speeds. Frequency is too fast to be U-Joints. When trying to duplicate it using the method above, it goes away when the wheel is straight, but progressively worse with decreasing radius while turning. Doing some digging, I learned that our anti-spin rear end is a clutch type. One theory of mine that seems to explain the symptoms would be that the clutches in the LSD rear end are chattering. (Cold clutches and fluid, tight radius turning, torque applied to rear end, making the clutches grip tighter and chatter against each other). I have also noticed that it is more pronounced when going uphill (more torque on the LSD clutches causing increased chatter) The only evidence against this is that I swear I have experienced it in a straight line once before. I do know that it happens primarily while turning, like when making a right hand turn from a stop at an intersection. Has anyone else experienced this?
When regular (non LSD) diff fluid is used in a clutch type LSD application, it will cause chatter around turns. Knowing this, I'm tempted to swap the diff fluid out with some synthetic with LSD modifier just to double check that it has the right fluid!
