While metal on metal may cause some blue loss, every time you use your ejector that happens. Except for safe queens most guns show some blue wear on the rod. Safe queens don't have their rod come loose.
I would check for burs and damage on a chuck, but the jaws are pretty hard. It is almost always the bit that gets a grrr when a chuck slips. I also tighten the chuck up good and tight when I use it so it does not slip. I have never done a grrr on a rod with a chuck
You could easily smooth up a chuck jaw with a small chain saw file or sand paper on a dowel
Another option is go to the hardware store and buy a piece of brass tubing, Ace has lots in various sizes. Get a piece that it just big enough to slip over your rod, cut of a 1 1/2" and split it with a dremel cutter and place it over rod before you put the chuck on, vise on. etc
I have a couple sheets of thin copper I cut up with scissors to use as shims or slip between work and lath jaws to protect stuff
The hardwood block thing works to, especially with a bit of rosin. I use pieces of oak in my vise to hold barrels when changing them and turn the frame with a frame wrench I have made both aluminum then nylon inserts for.
Take 2 pieces of aluminum brass, steel, oak or what ever, clamp them together and drill a slightly under size hole in the split where they join and your set. If you want something to use over and over first drill thought the pieces from the side so you can bolt the together then drill the clamp hole. If you leave one piece long or weld on a rod you have a handle and basically have made a wrench.
The one I use for rifle barrel is 2 pieces of heavy aluminum I drilled a hole though that clamp between 2 pieces of 3/8" steel bolted together by 4 3/8" bolts on each side. Clamp the reciever in a receiver wrench, heat it up a bit with a torch and then give the barrel wrench handle a good wack. This started life as a Remington 600 in 308, Now it is a 6.5 Creedmoor
Cylinder rods are easy to hold so you can loosen and tighten compared to rifle barrels