Hello all!
Are low frequency driveline vibrations normal with the Quadra-Trac II (NV247) / Dana 44/226MM rear axle, standard 4.7L V8 WJ when driven at high highway speeds? The vibration is only mildly noticeable at around 65-73 MPH, but the feel of the floor pan at 80 MPH is somewhat aggravating. The vibe is not in the steering wheel any more than any other part of the vehicle. The vibration is present even if the transmission is slipped into neutral, though appears stronger when the engine is either accelerating the vehicle or being used to slow the vehicle down. The only other thing that I noticed is that with the parking brake on and transmission in neutral, shaking the front prop shaft side to side near the front diff yields no play, but shaking it side to side near the transfer case yields a little bit of play. Since this Grand Cherokee is only a week old, I took it to the dealer. The tech was able to feel the vibe and identified that it was from the front. They re-balanced the front tires and indexed the front driveshaft (spun 180 degrees). They then drove another new WJ and told me that the vibe is normal. They have offered to let me drive another new WJ to prove it to me which I will do. This vibration was definitely not normal to a 2003 WJ with the same
4.7L/QT-II that I drove in regularly for a while, and it wasn't in my good old 5.2L ZJ. (I don't know if that one had U-joints or Cardin however.) Is this normal? Suggestions?Thanks!