Does a 2011 Hyundai iLoad differential have any yellow metal components (brass, bronze) in it?

It’s possible – although pretty unlikely - that a modern car still uses bronze bushings somewhere in the differential or drive-axle assembly. The material is likely to be bronze or phosphor-bronze.

I’m tipping you’ve performed a differential-oil drain and found a few metallic-looking bits in the bottom of the rain pan. This is never a good thing to find, as it suggests that something is wearing inside the diff and shedding these filings. It’s actually not abnormal for a few tiny fragments to appear in the oil, but if the bottom of the drain pan glitters like you’re panning for gold, then you have a potential problem.

Even though the fragments might look yellowish, they could have started out silver (like normal bearing material) but have become discoloured due to time and heat in the environment in which they operate. So, just because they look like bronze or brass, they could be made from any type of bearing material. At which point you need to investigate further.