As I've said several times, Vic, Shell replied that they dye red all fluids sold to the public, but do not dye fluids supplied to the OEMs.

Smith & Allan are the official Shell distributor for the UK. This is Shell original formula M1375.4.

You can also email or call them to verify why it's red:

It's best you do that so you can provide future confirmation too, Vic.

Westway Lubricants supply undyed fluid to the same spec, but they blend their own and are not a Shell distributor. So their fluid may not have the same modifiers or additives as ZF LF6.

Dinnae' wurry about the fluid itself though, I already tested it.