I'm working on a pre-HDi Peugeot 406 2.1 turbo diesel estate at the moment. It runs quite well but the brakes were/are pants and the HDi is probably quite similar. It was possible to re-use the front calipers as probably the engine heat means that they don't rust as badly as the rear calipers. New discs and pads plus careful fitting sorted-out the front.

The rear is a different story and the brakes are a heap of junk. The handbrake shoes eventually wear a tramline in the brake drum (integral with the disc) and this makes the disc quite difficult to remove. Incidentally the brake shoes are about the size that is suitable for a moped and presumably this is what causes the poor handbrake trouble. Replacing the shoes is a tiresome job and I suspect that at the factory the hub goes on afterwards. The problem as usual is hooking-on the return springs. Unlike on antique British cars the piece-of-string-method and the wire-coat-hanger-method won't work as the springs are too strong.

Obtain a long slender screwdriver with a shaft about 5 mm thick. File or hacksaw a slot in the centre of the blade. You now have a spring replacement tool! The next problem to be noticed is that the brake shoes will squirm about and go awry making the job very awkward. Obtain a luggage belt or a ratchet belt that is about an inch wide and put this over the brake shoes. Once the belt is tightened the shoes become rigid and one is then in with a chance. It is easier to push upwards when replacing the spring as one can then brace ones elbows against ones legs and give a strong two-handed shove. There are of course proper brake spring pliers out there somewhere (probably in a car factory) but such tools are seldom seen even in tool catalogues.

The caliper itself has infernal sliders that rust and seize. The hydraulic piston can also seize when rust gets underneath the chrome. It is not really a good idea to drill the old caliper slider area for grease nipples as the caliper might then be unacceptable for exchange, grease nipples can be added to the new one! At the time of writing a new piston costs £16 and a seal kit about the same. If an exchange caliper can be got for £50 (ish) it is hardly worth messing. Considering how much salt is put on the roads cars really need stainless steel marine brakes but pigs will fly before that happens.

Good luck!