So I picked up Uthgerd when Lydia and that other dude from Candlehearth Hall died in a swarm of Draugr. Only, her armor is not showing up when I go to trade with her. Shes wearing steel plate, I guess, but it does not show the name. I try to give her Dwarven boots but she won't put them on.

My only guess is I have to give her an armor that is higher rated than steel plate...is that correct? Then she will switch armor. Otherwise she will ignore the lesser armor. But why won't she put on the Dwarven boots of weight (allows you to carry 40 points more)?

The armor you give her has to have a higher rating than her default armor, and the same goes for her boots - the ones you give her have to have a higher armor rating than her default ones. Any enchantments on these items won't make her (or any follower) prefer them over items with a higher armor rating.

Also, their default items will never show up in their inventories, even if they replace those items with better ones that you give them.

Oh, thanks so much. I guess I thought that might've been the case but I'm glad you confirmed it for me. Cheers!