Mine did the same even though they were greased. I found it was cheaper to buy the entire Harbor Freight WDH than pieces to fix mine. By chance, the spring bars were the same diameter, so I continue to use the old spring bars and hangers with the new head and stinger. My old head and stinger are now adjusted to a different height and I use it for dead tongue weight pulls of lighter trailers.
I did not catch my egged out holes until I dropped a spring bar going over uneven terrain. I was going slow and had the window open, so I heard it drag on the ground.