You must have a 48GT deck. I have a 54GT on my 1864, so pretty much the same, except for cutting width.
Doubtful that Cub Cadet put an extra layer of metal over the stamped deck to give it longer life. It's either powder coat or the steel de-laminating due to deterioration. Using the deck to cut up leaves and such can make certain areas of the deck look a shiny silver color, like fresh bare metal. Maybe like a thin coating of metal...
When I restored my 1864 deck, I removed all the bearings and other pieces that were attached and pressure blasted the shell. Then I used "tiger hair" fiberglas in a few areas to smooth them out. I sanded the fiberglas for better paint adhesion and sprayed the underside with 2 full coats of epoxy primer. I lightly sanded the primer, then put 3 full coats of gloss black rustoleum with hardener added to make the underside of the deck very slick to prevent grass form sticking.
The deck held up very well for the first 3 years of use. Just last year I cleaned, re-primed and re-coated the areas around the blades where it was starting to wear down to the light grey primer. Hoping it will last another 2 or 3 years before I have to do it again.
It is a good idea to keep your deck in good shape as they are hard to find if you need a replacement. Power washing and painting/touch up at the end of the mowing season is the best way to prevent further deterioration and keep it looking good and functioning properly. It goes without saying that blades, bearings, grease and belts should be checked as well.
