WK2 transmission thump and sings in 4th gear
My 2014 GC diesel transmission is giving me a thump into the rear diff at mostly slow crawl traffic speeds, on and off the fuel between 1st, 2nd and 3rd. Very similar to having too much play in the rear diff like an old Ford Falcon. It's most obvious when the revs have dropped back to idle. Punch the throttle a little hard to move up in traffic and, bang! The transmission doesn't feel ready and is caught out and disengaged. I have driven another GC diesel of similar vintage that was as smooth as silk in traffic. No problems at medium to high speed. All software updates have been performed but this feels more mechanical. I read on one thread of a similar problem being fixed with a 'valve body' replacement (whatever that is).
On a different note, a singing like whine has developed in 4th gear coming from the engine or transmission area at around 40-60kms/h and tapers off when it changes to 5th and then disappears. Very odd and very specific to 4th gear. Sounds like turbo whine on a big semi but more subtle. Any advice welcome as the Chrysler Jeep techs are scratching their heads on this one.