So, I had my Mk3.5 serviced last week by a Mazda garage and was advised that the rear offside brake is binding, allegedly to the extent that the brake pad material has melted and it was barely possible to rotate the wheel when it was on the ramp! Seems a bit dramatic especially as there has been no hint of this in terms of brake performance, handling and so on. I haven’t had the car on the jack and the wheel off to check but having driven the car some 10 miles back home after the service there was no obvious visual sign of excessive binding, no smell of burning brake pads and the wheel/caliper was not abnormally hot to the touch compared with the nearside. I was also able to put the car in neutral on a slope and it would roll without coming to a premature stop or pulling to one side which I would expect if one brake was binding.
Leaving aside that it may simply be the caliper is a bit stiff, I was told that if it needs a new caliper I should replace both sides otherwise it will affect the balance of the car. That sounds like a bit of BS to me as if it were really the case you would only be able to buy callpers in pairs whereas you can buy them individually. The prices quoted to do this are absurd (£108 + VAT just to remove the offending caliper to check it’s condition). I know from previous experience that it is not a big job to replace a caliper and good aftermarket or reconditioned calipers are moderately priced. So, my question is, if I opt to do the work myself, is there any strong reason why I should replace both sides? Is this just something that people do for peace of mind, or dealers say to make more money? Interestingly, my local independent garage also suggested replacing both. Given the cost of the calipers I can get, it wouldn’t be a big issue but at the same time, I don’t see the point in spending the additional time and money if it’s not really necessary.
I defer to the experts on here. Any thoughts and advice would be appreciated.
If you get them to replace 1 and the other fails shortly afterwards you’ll be getting it done again and having another set of pads due to uneven wear. If you are doing it yourself you can ascertain the status of the other side easily and it’s only your own time spent rather than £100 per hour you can probably do 1 at a time.
Personally I would do both just so that they are the same and I would do the discs and pads too so it’s all shiny. New fluid all round too as you’ve broken into the circuit. That’s me doing it myself though. Paying workshop hours tends to dull my enthusiasm for shiny
I think the first thing I would do is to remove the offending sides wheel and check the caliper slider pins for binding or sticking. You would also be able to gauge the condition of the brake pads and the caliper piston seals… Depending on what you discover you could find that just cleaning up the pins and re lubricating with either rubber grease or Createc will solve the problem if one actually exists. If the pads are badly worn and you fix the slider pins and the caliper pistons look ok you need to repeat this on the other side and replace the pads on both sides. If the calipers are really badly seized then replacement is your best option unless you fancy stripping them down and fitting replacement piston and seals. You will need a piston wind back tool of some kind if you replace the pads. Some use a large flat head screwdriver or a cube type tool from Halfords is probably easier. In any event you need to confirm the garage diagnosis as correct before you decide what to do, however chances are if one rear caliper is going bad the other may not be far behind.
Thanks all. I’ve ordered one replacement caliper and new pads. I know the discs are fine as they were only replaced recently. I’ll have both callipers off and check the condition. At the very least I can replace the one if needed. If the other looks suspect it’s easy enough to get another. Just totalling up the labour cost makes it worth doing myself, which I did before on my NB.
Had the Mazda garage calling today wanting to book the car in, and that’s without telling me what the potential costs are likely to be. I’m giving them a wide berth for now. Weather looks good for the weekend so I’ll have the car up on the ramps and get stuck in. Been a while since I got my hands dirty mucking about under a car!
Thanks. Useful reference although I’ve changed callipers before so wasn’t actually needed. Car all done. Re-bled the brakes while I had the car on stands. All nice a tight now. Just need to book it in for its MoT and then it’s good to go for another year.
The only thing pulling the piston back off the pads is the elastic reaction of the piston seal being twisted as the piston moves out.
When the piston seals hardens the elastic reaction decreases especialy when hot.
Therefore hot discs due to the pads dragging.
The other issue and it was the second issue on the rear calipers on my Mk3 is that the internal mechanism in the caliper gets gummed up and the metal spring that pulls the handbrake mechanism back is not powerfull enough get the handbrake mechanism released.
Yes Eddie that was your experience, but what about the original poster? Still want to know about the nearly y melted brake pad material and and an unrotatable rear wheel. Was the original garage report correct…