Recently done the front brakes on my Uno 60's. Which has brought back just how easy they are to do yourself.
There's really very little to the braking system on the Uno, so my assumption is that as long as the (a) Disc's are new (b) Pad's are new, and (c) Calipers are in good condition, you'll stop the noise from coming back again.
Here's a detailed guide for you (assuming you're replacing front PADS & DISCS only).
1. Get the parts first! You'll need:
(a) Two new solid Front Discs - there is only one type for all the Uno models except the Uno Turbo ie (Price: Between £5 - £9 per disc)
(b) Four new brake pads (a pair for each side) - there are two types for the Uno models, except for the Uno Turbo ie, but the two types are both compatible. They'll usually come as a pack of four. (Price: Between £12 - £20 per pack).
(c) One brake pad fitting pack, (you'll need this to prevent excessive brake squeel and rattles, and to ensure the calipers are correctly seated back in their carriers), the pack should consist of four brake pad anti-squeel spring clips, and at least for split pin type clips). (Price: Between £2 - £3)
(d) One small tube of Copper Grease, (again this will prevent squeeling, and seizure of most of the components). (Price: £2 - £3)
The job (repeat for both front sides):
1. Loosen the front wheel bolts, but don't remove the wheel.
2. Jack the front of the car up, using a suitable trolley type jack, or axle stand, and ensure the car is secure when jacked.
3. Continue to undo the wheel bolts, and remove the wheel to reveal the brakes, and hub assembly.
*Removing the Caliper*
4. The Caliper on the Uno is held in the Caliper carrier by two metal shim pieces. The shim is held in with a split pin.
5. With a pair of thin nosed pliers, remove the split pin from the top and bottom shim, at the rear of each shim.
6. With a flat blade screw driver, and hammer, tap the shim from it's rear it will move outwards, and release the caliper. Do this for the top and bottom shim.
7. Push down on the Caliper, and lever the top half out of the Caliper carrier, then fully remove the Caliper, and rest on the hub/disc top so as not to put strain on the brake hose. *DO NOT LET THE CALIPER DANGLE FROM THE HOSE*
*Removing the Caliper Carrier*
8. In order to remove the disc, you'll need to remove the caliper carrier so that all the disc is accessible, and removable.
9. At the rear of the disc/hub assemly you'll see two large bolts holding the carrier on the hub. Undo these bolts. *These are likely to be very tight, and partially seized*, if you have problems here, spray lots of penetrating oil on the bolts, leave for a few minutes, and repeat the spraying of oil until you're satisfied that the bolts and hub and soaked enough of the oil up and try again. They should undo.
10. Remove the caliper carrier, put to oneside.
*Removing the Disc*
11. There are two locating bolts on the brake discs. One will have a pin stick out of it, the other will be a standard bolt. These need to be undone. Be careful when undoing these bolts, they have a tendency to "round off", as the metal they are made from is quite soft. Use the correct socket sise, and you'll be fine with this.
12. Once the bolts are removed the disc can then be withdrawn from the hub. If the disc hasn't been replaced for a while, it's likely it will be partly seized onto the hub. With a hammer tap the rear of the disc all round, this should loosed the disc, and it should come free.
*Cleaning up process*
13. Before I replaced all pads and discs, I gave the complete brake assembly a thorough clean up. You'll need some engine de-greaser, or brake fluid, some old scrubbing brushes, sandpaper and flat blade screw drivers. Start with the hub itself and give that a quick scrub and clean. When dry, put some copper grease on its face. Then give the caliper carrier a clean. Pay close attention to where the caliper would need movement to brake, and once those areas are cleaned, add a little copper greae their two. Lastly, give the caliper a good service and clean. Check the rubber seal is intact and not distorted at all. If it's just distorted, you may be able to ease the distortion out, and get it back to it's original shape, if the seal is broken, it should be replaced with a new one. They are generally available from a parts specialist.
*Preparing the car for new parts*
14. With clean hands, get the new disc, and bolt it up to the hub.
15. Now re-fit the Caliper Carrier, ensure the carrier is well fitted and tight.
16. Working with the caliper now, you'll need to push the piston further back into the caliper, as the new thickness of the brakes and pads needs to be accomodated. Either buy a brake piston push back tool, (£7/£8), or using two levers and brace them against the edge of the caliper and push the piston in. Personally I'd spend the £7/£8 - it makes the job far easier, and you'll be able to use them again for most other cars.
*Final fittings*
17. With the piston fully home in the Caliper, with clean hands, get the new pads, and on the top edge, clip the anti-squeel pins on. The potruding part, needs to be on the outside edge of the pad - so that it's visible.
18. Now fit the pads into the Caliper carrier - they'll only fit one way.
19. Smear some more copper grease on the outside of the pads. *DO NOT LET ANY GREASE GET ON THE PAD, OR DISC ITSELF*
20. With Caliper ready, start with it's bottom edge and slide the caliper back into the Caliper Carrier, the Caliper with then slide over the new pads.
21. Once the Caliper is in place, you'll need to tap the metal shims at the top and bottom back in place. Start with the top one, and if needs be use a flat blade screw driver to lever the Caliper a little to make room for the bottom shim.
22. Once both shims are home, tap the new split pins into the holes on the rear edge of the shims, to lock them in place.
23. Check that all is sound, and the disc moves freely, de-press the brake pedal a few times until it feels stiff again.
24. Smear a little copper grease on the disc hub face (not the braking area), this is so the wheel doesn't seize on the hub.
25. Refit the road wheel making sure the road bolts are tightened.
26. Lower the car, tighten the road wheel bolts further, start the engine, and test the brakes a little.
Now you'll need to repeat the process for the other side.
It sounds complicated - but it's easy, and this has really been broken down in detail above.
Good luck.