Gore-Grunta Fur vs Endurance Brown

How close are they?

ΔE 16.5, loose: different enough that you should pick on purpose. Endurance Brown is noticeably darker, more muted than Gore-Grunta Fur.

Can I use Endurance Brown instead of Gore-Grunta Fur?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Endurance Brown is noticeably darker, more muted than Gore-Grunta Fur.

Can I use Gore-Grunta Fur instead of Endurance Brown?

The same difference applies the other way round: Gore-Grunta Fur is noticeably lighter, more saturated.

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.