I have just read in a Haynes' manual that the hub nuts on my (1999, 1596cc) focus estate are 'laminated' and can only be reused 4 times max.

Does anyone know what a 'laminated' nut is (excuse my ignorance) and why it can only be reused 4 times? I've just had the brake shoes replaced (not by a main dealer) and having taken the car back to get the handbrake readjusted afterwards I've now added two 'lives' to the nuts but I don't know how many times they had been removed and replaced previously - there's got to be a good chance the total number now exceeds 4 as they have been reused at least once before while I have had the vehicle (when it had a major service) and prior to this the vehicle was regularly and properly serviced up to 120000 miles (with rear bearings replaced at 54000 ('including hub') and 80000 miles respectively).

Secondly I was advised at the major service a while ago that my drums were 'worn to the limit' but when the shoes were replaced the garage (a different one) assured me the drums were in very good condition - but they took no measurement. When I asked them about this they were adamant the drums were fine - with no sign of any 'lip' on the outer edge for example - and that I had nothing to worry about. Should I insist on the drums being measured - what are the consequences of having the drums wear beyond the limit?

heres the technical side of laminated nuts

A laminated nut having a plurality of conical spring discs for use with a bolt assembly. Each of the discs is formed with a hex shaped outer periphery and a non- round central bore. The discs are assembled on top of each other forming a laminated stack. A threaded tension sleeve is located in the central bore and has a non-round outer periphery shape corresponding to the shape of the central bore of the discs. The tension sleeve has a threaded inner peripheral wall with the threads sized to fit the bolt assembly. The tension sleeve includes an upper flange to engage and hold the upper portion of the laminated stack and a lower flange to support the laminated stack. Application of a torqueing force to the outer, hex shaped periphery of the discs forces them to deflect and contact the threaded tension sleeve applying force along the length of the bolt assembly in a uniform manner to reduce clearance between the bolt threads and the threads on the nut tension sleeve

as for the drums i carnt see how they can be worn to the limit without being some kind of lip on them