Shudder
 

Over 12k on my new truck and I'm very satisfied...except for the shudder! Happens when I'm loaded and pulling away from a stop or at speed when climbing a long hill. Read a few postings here about carrier bearings or u-joints being the culprit. Or is my tranny slipping? I read somewhere that dealers are putting Dodge differential additive in them. Anyone else having this issue?

Drive about 5-10 MPH along side a building with your window down and listen real close for a squek, squek, squek sound. If you hear it then it's your u-joint.

The differential additive is for when you go around corners and the rear end binds a little. Anit-slip additive helps eliminate this.

If your tranny is slipping climbing a hill at speed with the TC locked (should be in 4th and higher) you will see your RPM's climb but the truck not gain speed, that is as long as it dosen't down shift.

Isn't the anti-slip additive only for use in a clutch style differential? It's my understanding the AA style differentials, which have been in the Rams since the mid-2000's, do not use clutches...so they don't require/use additives. (The Amsoil site does not recommend their anti-slip additive for use in the AA 11.5 Anti-spin rear.)

Your right the AAM axles don't require anti-slip additive. Good catch, I've been away for awhile.