I too recently bought a 2004 limited with a Hemi, and notice a similar thing now and then. Not all the time thought. I also have a 2005 Grand Cherokee, and it works perfectly. It slows down without any hesitation.

 

My '04 slows like a rock (well maybe not that bad) when I let off the gas pedal. Sounds to me like something's sticking or the electronic throttle is acting silly. Hmmm, I wonder if there's any contact points around the pedal that need cleaning?

 

Being that you got it used, it may have had a performance flash or some other work done to it. My 04 was normal until I did all the stuff to it.
Mine used to idle @500-550, now since the flash it idles @ 750-800 rpms.

 

Thanks guys, I've read several posts on poor shifting and flashing to change the shift points. This thing shifts really nice and holds a gear well when towing.

As is the reason for the post, if I'm running the freeway at 65 I'm turning ~1700rpm. If I let off the gas, I'm still running ~1700rpm for quite some time. Stepping on the brake does cause the rpms to drop, but it is as if it's forcing it to slow down.

 

Mine's the same way, and I have read where others have recognized the same behavior. I also had mine reflashed which helped the trans hold gear when towing, and also improved off line and low rpm acceleration. However, no change to the closed throttle decel (what little there is). Don't know why it does this, but it could be related to emissions.

 

Being that you got it used, it may have had a performance flash or some other work done to it. My 04 was normal until I did all the stuff to it.
Mine used to idle @500-550, now since the flash it idles @ 750-800 rpms.

I see the same after modifications to the engine, it might have to do with vacuum leaking issues or a bad MAP sensor. Vacuum controls the idle on our engines.