Brake Disc DIY Replacement

[acra]

Hey guys, I've got a C3 new shape so it's the same platform as the DS3...

Looking at the official workshop manual, Citroen are warning that a brake disc (and even pad) replacement requires all screws/bolts to be replaced (apart from the normal wheel bolts) and the threads tapped!
I've never had to do this on a brake replacement before, but wondered if anyone here had any ideas why this is, and if it should be done?

Rest of the job looks straightforward, plus I've managed to source OEM Bosch parts for £65 so I'm happy there! :cool:

[DaveB]

I've come across it with other cars. The reason is that new screws/bolts have a thread lock coating (blue on the ones I've used) which will not perform properly when they are re-used. I've never come across an instruction to run a tap through the holes before re-fitting, although it does make sense as a sure-fire way to remove muck & rust.

OK, that's the manufacturers' CYA way of doing things. In reality, I've never had a re-used fastener work loose. I just give them a thorough dousing with brake cleaner &, on things like caliper mountings which I don't anticipate needing to unfasten all that frequently, just a dab of Loctite.

Usual disclaimers apply!

[acra]

Cheers Dave, makes sense - I'm an IT tech so normally work on laptops and the like, it's the same there where we use blue loctite type stuff to keep things from vibrating loose.

I wondered if it was because the screws/bolts are being taken past their elastic limit, but would've thought that's a pretty bad way of keeping them tight!

The manual also talks about replacing with 'pre-coated' screws, wonder if that's just some kind of anti-seize?

[DaveB]

I wondered if it was because the screws/bolts are being taken past their elastic limit, but would've thought that's a pretty bad way of keeping them tight!

Common practice on cylinder heads but never, to my knowledge, on brake systems.

The manual also talks about replacing with 'pre-coated' screws, wonder if that's just some kind of anti-seize?

That's the thread lock!

[Sash]

If you're worried, drip a bit of loc-tite on the thread before replacing them.