Just bought a secondhand one, the train has needed a good scrub. Googled this and so tried wd40 but that wasn't that effective. Tried some terps which has done a little better but still not perfect. Any more tips from anyone?
It's not too bad, I will light it anyway so you won't see it.
Depends on what's caused the stain really, most Hilite trains I see have friction marks from heels and so on.
I would have tried white vinegar first, definitely not WD40 as you'd have to clean it at least twice to get rid of the residue. Maybe Acetone if you've got glue/paint on it, I don't think it'll react with the vinyl but may dry it out (in other words, double check before you try that).
Have you tried 'magic eraser' melamine sponges?