checking the back brakes of Mazda 3

[captain jack]

Hi, I am pretty much a n00b when it comes to all things mechanical, however know a few vasics about brakes etc. I was thinking about looking at my missus' rear brake pads (just been done not long ago) to see what the possible rattling is that seems to be related to the drivers side caliper.

The main question is this, do I if only taking the pads out to check the caliper, have to use a caliper rewind tool to reset the position of the caliper if I am just checking and not changing the pads?

Secondly, has anyone had issues with brake cable rattles or is this likely to be something more meaty attached to the brake calipers and pads causing the rattle?

All help would be gratefully appreciated.

Ta.

 

[rodenal]

If all you do is remove and reseat the pads you wont need to wind the piston back. It's pretty unlikely anything within the caliper is the source of a rattle though - does the car have heatshields at the back? These are more likely to be your problem if it's an actual rattle rather than knocking.

I suppose one of the caliper bolts could be a little loose but you'd certainly notice that and it would be far more than a slightly annoying noise. First thing I would do is get the wheel off and check around the area for anythign loose, by all means flip the caliper off and check the pads but there isn't really anything in there to make that kind of noise unless they are the type with a clip and this has broken (even then, the pads are held in tightly by force alone).

 

[Matt82]

if a calliper bolt was loose then id be expecting a knock every time i got on the brakes and i wouldnt drive the car

 

[rodenal]

I've (unintentionally obviously) done it before, you get far more than a knock under braking - any shift in weight at all and you can feel it so it's pretty unlikely to be the cause, thought i'd mention it anyway as you never know.

 

[captain jack]

Thanks for the replies, the rattling does sound very tin on metalish, weird thing is that it goes away if you apply even a tiny bit pressure on the brakes. I thought initially that it was something to do with the handbrake cable.
I tightened the handbrake up and it went away for a bit but is back again bad as ever.
The hand brake tension has remained the same though. I will check if the bolts are OK, the calipers do seem to be solid enough when checking them.

 

[rodenal]

Just be careful your handbrake will be self adjusting - you should never need to tighten it. If the handbrake was innefective it may be a sign of a problem with one of the calipers but you'd likely notice other problems too - if anything the mechanism would sieze on or off so very unlikely to cause a rattle.

It still sounds like a disc heatshield problem to me tbh, try carefully bending them back a bit (unless of course it doesn't have any). Watch your hands they tend to be great at cutting right through skin

 

[red eye]

Thanks for the replies, the rattling does sound very tin on metalish, weird thing is that it goes away if you apply even a tiny bit pressure on the brakes.

Sounds as the pads could be knocking about in the caliper. Some brakes have metal shims on the pads garage prob forgot to put it on, you can cut up a coke can or You can get anti vibration sticky pads from halfords