Telling the dvla about a engine/fuel type change

[bashbarnard]

Swapping tax band and engine are two different forms. If you are not in trade its always best to get a safe for road letter drafting up from an mot station. Therefore when you send it off they wont ask you for a load of extra. Can all be done on v5c. The tax form is a different form though cant remember which one off top of my head but you need proof of what year the engine came out of as tax will be done on what's older. So if its cheaper tax atm and the hdi came from a 1998 then the tax will go up.