Upgrade at work help please!

[lulu_bucket]

Do you know how we can put in for an upgrade at work,
Medical Secretaries there are a mix of Grade 3 and Grade 4 but the Grade 3's do exactly the same work and this grading was only changed with the agenda for change so if basically someone left the post it was re-advertised as a Grade not 4 - only difference is that the top of Grade 3 pay is about 3,000 less than the top of Grade 4 and it is not at all fair. Work for the NHS at one of the busiest hospitals in the country - any ideas please. It has been done in other divisions within our hospital successfully - but our division apparently is in debt but then who isnt!?