hello,

I have a weird symptom developing. It goes a little like this...

1.) When accelerating (light or heavy) from a stop the truck begins to move as expected, no problem from initial take off...

2.) just after the truck begins to move (say around 2 - 3 MPH) there is a drivetrain "jolt" much like one would expect to have with worn U-Joints; however, the U-joints are fine. There is no audible clunk or any other noise but a jolt can be felt just after take-off. It almost feels like the engine mounts are loose/worn, when enough torque is applied the drivetrain shifts and a jolt can be felt.

Has anyone experienced this? If so what was the diagnosis and/or fix?

Thanks in advance.

 

Not too familiar with the 48RE, but we had a rig at work that did that. Turned out to be a shift solenoid.

 

Last time I had a problem like this it was loose U-bolts around the rear diff. Try a check on them.

 

Not saying that this is your problem, but I had a Dodge Ram Charger that would do exactly as you describe. It was the splines on the drive shaft that would bind and as the vehicles weight would shift aft the splines would suddenly slip and cause the bump. The yoke was changed several times under warranty and the bump would go away but would return after about 15k miles.

 

Thanks all for sharing experiences/ideas. I'll check the slip yoke and U-bolts.