I have a 2005 Jeep Wrangler Sport with just over 58000 miles. It has a stock 4.0L in-line 6 cylinder with a manual 6-speed transmission. No lift kits or suspension mods. I have been noticing a strange rattle coming from up under the front end when I am cruising through parking lots or coming to a stop at an intersection. When I get down to around 10-15mph the rattle becomes audible and you can feel it in the floorboardYou just feel it. It doesn’t matter if the clutch is pushed in or not. When accelerating or cruising at highway speeds (anything 20mph or up) the rattle goes away. Only when decelerating or coming to a rolling stop. Any ideas guys (or girls)?
Loose catalytic converter heat shield.
It could be most anything, but @jesmed 's suggestion of the heat shield is the most likely. When checking the heat shield, look to see if all the exhaust hanger hardware is intact too.
i just went outside and crawled up under it and “shook” everything I could get my hands on. The exhaust from the header and down to the converter was the only thing that would even move, but if I put enough force on it, it would shake just a little, but it wasn’t hitting anything. I’ll try again and go closer to the converter and check around it.
Thanks for the advice!!!
I have owned several Jeep Cherokees with the 4.0 engine. All of them eventually had a rattle in their cc heat shields before they reached the 100K mark. I think jesmed is spot on with his/her advice.
My '02 Wrangler X that I bought new has 219,000 on it and, as such, my best advice is: it’s a Jeep. Turn up the radio! 
Could be something like the CC heat shield. About 100k ago my shield used to buzz a little when you slammed the doors. I jiggled it a little and the rattle went away. Could also be a u-joint, though you’d probably hear it rather than feel it.