The manual says discard the nut, or bolt when changeing brake pads, calliper, front bushes and heaps of other places. Does anyone actually do this or is it safe to re use them ? and where do you buy them , would holden keep these in stock ?
yeah thats what i do, i'm just not sure that method would hold up in court thats all. Some of the bolts in the brakes and suspension actually stretch a tiny bit when you torque them up. So if you keep using the same bolts again and again they will eventually snap... either when you torque them , or when your half way round a corner at 100k's. Its never happened to me tho, just wondering if holden has kits of bolts for the common jobs on a commodore ?
I doubt that they still stock them all, there are numerous bolt shops around the country that will be able to match something up for you, will probably cost you about $1 - $3 per bolt from these places, as opposed to holden who will probably charge you $10 for a pair of bolts IF they even still stock them.
I've never seen anybody replace a caliper bolt and never seen one fail. Some of the caliper bolts on cars I've worked on have looked to be as old as the car they were fitted to. I sincerely doubt anybody actually changes them. Ever.
'torque to yeild' some bolts are classed as 'torque to yeild' once the bolt has been removed it is highly recomended that you replace it with a new bolt of the same strength integratie as it once its be torqued up and then undone its deemed spent, i believe it has something to do with the structual properties (cant recall exactlly) normally cross member bolts have these and some suspension bolts on car. personally ive never replaced a bolt on the calipers or brakes, ive always reused the same bolts on my cars but just with loctite, cross members/k frames i do replace them though
I know that sometimes the bolts on calipers, mainly the "guide pin" can end p slightly bent, at which stage replacing it is a good idea, otherwise lube and or loctite.
"torque to yield" is only really critical on engine components, like the flywheel. Sure can't hurt to change your caliper bolts every time you take them off, but who'd wanna? It's not like they're going to shake lose if you do them up tight enough. All bolts stretch a little when you tighten them up.
What you are talking about there is when a piece of metal (ie bolt) is torqued beyond it's elastic limit and goes into the "plastic" zone. This is that area between when the bolt will no longer spring back to it's original size/shape, however it has not broken as such. Take a look at a bolt shortly before it breaks - the thread (or area which is about to break) will look like a piece of licorice. I can only think of a couple of times when I have replaced bolts on brake calipers. I do a visual inspection before re-using them though, looking for signs that it has been tightened past it's elastic limit. Morton is on the money - I've never heard of one failing on Commodore brakes either although I'm sure it has happened somewhere. Reaper
