Weird Thumping Sound...

I have a 2004 5 lug that I daily drive. I've noticed over the last couple of days that towards the end of my commute, when I push my clutch in at a complete stop, my truck makes this thump noise. Like something dropped from the truck. Nothing actually drops from the truck, but that is what it sounds like. I've been driving it still and I'm not too worried, but it doesn't exactly make me feel good. I'd like to fix it because, well, I want it to go away.
Any ideas what it is?
Thank you for your time.

 

Possible it could be clutch component sticking, perhaps the slave cylinder. But if it shifts/sounds OK while underway, likely not the issue. Inspection of fluid level, condition of cylinder and hose still be in order.

On rare occasions one of my rear drums does release late and is audible & felt as faint thump. Mostly happens after releasing e-brake or resuming forward after backing up and coming to complete stop. But has happened in stop/go traffic.

Not sure of your local, but cold weather does impact the functionality & sounds too...factor in the wear, age and miles...this applies to me too!

 

Yeah, my shifts are normal. It hasn't been cold lately. I am at 145k on the original clutch but again, it shifts fine. Thanks for responding. I'll probably just keep on truckin, but if it gets worse or something I'll look more into it.