Hi guys,
Hoping to pick the collective hive-mind with a weird brake issue I'm having. I'll set the scene:
1. 2010 Mazda 3 GX
2. ~130,000km on the car
Back in April when we had the ice storm in the GTA, the left rear tire was not spinning.
Jacked the car up, and checked out the brakes and the left rear was clamped tight and not releasing. Later found out it was the hand brake spring component that had seized in the engaged position.
Took the caliper off and decided to replace both of the rear calipers. Ended up going with some Centric remanufactured calipers instead of Mazda OE. Remanufactured calipers are essentially OE calipers that have been rebuilt (new piston, seals, handbrake hardware, and this set came with a fancy zinc dichromate coating, so hopefully less chance of corrosion related issues in the future)
They were fully loaded calipers, so we got new hardware and pads. Installed the new calipers, and also decided to flush the brake fluid (used a non-silicone, glycol-based DOT 3 fluid from Lucas).
Followed procedure for split-diagonal bleeding (rear right, front left, rear left, front right).
After bleeding, we noticed the pedal did two weird things:
1. It reached the "end" a easier than it used to, and
2. After reaching the end, you could hear an audible click, and the brakes did not regain "pressure" unless the pedal is about 3/4 released.
Basically once the pedal reaches the "end", it's completely "floppy" and has no resistance, until you release the pedal to about 3/4 of the way.
One thing to note is that the car stops when the brakes are applied, and we even tried a number of high speed stops too, as well as engaged the ABS system, without issue.
We also happen to have another 2nd gen GX (MY2013), which does not do both of the things described above.
Threw in the towel about three weeks ago and decided to go to a Mazda dealer. So far they have:
1. Bled the brakes - no change
2. Replaced the ABS pump module - pricey and no change
3. Finally replaced the brake master cylinder
As of the last replacement the dealership is saying it has improved, but not fully recovered. I haven't gone to check the car out yet, but given the hesitance of the service advisor, I'm assuming the exact issue is still present.
The service advisor is beginning to doubt the rear calipers that were replaced, but that doesn't really make sense.
I have colloquially spoken to a first gen Mazda 3 owner, and a second gen Mazda 5 owner, who described similar problems after a brake change on their cars. One said his problem went away after a week; the other after 2 years. :|
Unfortunately I don't know if they had the exact problem, because I've not felt their brake pedal, nor have they felt mine.
Any thoughts?
Thanks in advance!
PS - Any gen 2 GX MY2010s in and around the Peel region, I'd love to try your brake pedal to make sure I'm not bonkers.