06 Grand Cherokee trans shifts hard in manual mode but smooth in D(Drive)

[ThomasWX]

I visited a private seller who is selling his 06 Jeep Grand Cherokee 5.7L V8. It has 165k miles, no accidents, regularly maintinenced. During the test drive, I noticed the transmission shifts great and smooth in D(Drive). But when shifting in manual mode, no matter gear up or down, it shifts hard, and the car feels like someone pulls back and then release in half a second every time it shifts. I was wondering if this is the sign of a controller or mechenic problem. Or is just how this car works. Thanks in advance!

(I have experience of driving auto trans cars in manual mode. I can tell this is not the engine break effect, it feels very different.)

[superj]

no idea from me. never been in one of those