Re: Thunk when upshifting
Is it 4 wheel drive?
I'd check for slop in the T case.
Have someone under the Jeep looking at the front driveshaft. Apply the parking brake and also press on the brake pedal as you shift it through P,R,N,D and back again several times.
If it moves excessively and thunks back and forth there is to much slop.
Take it in to the dealer as it is a new vehicle and at the least have them note the issue as they probably wont do anything to fix it...never know though you might get lucky and they will fix it.
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