ΔE 10.3, fair: the same colour family, but not a straight swap. German Uniform is a little lighter, more saturated than Petroleum Gray.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). German Uniform is a little lighter, more saturated than Petroleum Gray.
The same difference applies the other way round: Petroleum Gray is a little darker, more muted.
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 Petroleum Gray on the colour wheel See German Uniform on the colour wheel
All matches: Petroleum Gray equivalents · German Uniform equivalents