Any harm in adding rubber washer below deck leveling arm bolts?
 

I'm a new Cub Cadet owner. I just bought the XT1 Enduro Intellipower mower (brand new).

I noticed a rattling noise the first time I mowed with this mower, and after a little while, I realized that because my lawn is a little bumpy, the deck was bouncing up and down. I then looked by the rear tires and found that the deck leveling rods only have bolts on top, so they freely move up through the tube shaped holder that they are running through. This means when I mow, the leveling rods are bouncing up through the holder, then dropping back down, and when the bolts hit the top of the tube shaped arm holder, they are making the rattling noise.

Is there any reason not to put rubber washers below those leveling bolts to lessen the sound of the the bolts hitting the metal tube?

My last Craftsman mower never had this issue with the same lawn, so this is something new to me, and I'm not sure how else to deal with it.

Any other ideas would be appreciated as well.

This should be the dealers problem, improper deck installation and alignment.
I'd for sure make it his problem pronto.

Everything looks like it's installed properly, and it matches the assembly guide in the book, so it didn't occur to me that it would be an assembly issue. I just thought it was related to my somewhat bumpy yard, but I will look into that with the place I bought it from.