ΔE 8.6, close: similar, with a visible difference side by side. Mud Brown is a little lighter, warmer than Fur Brown.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Mud Brown is a little lighter, warmer than Fur Brown.
The same difference applies the other way round: Fur Brown is a little darker, cooler.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Fur Brown on the colour wheel See Mud Brown on the colour wheel
All matches: Fur Brown equivalents · Mud Brown equivalents