Brakes not working properly when wet

[Mazdarese]

Hello

I noticed the other day whilst driving (Mazda 6 MPS) at 70mph onto a slip-road, in the heavy rain, that my brakes really don't work in the wet. This surprised me somewhat.

In the dry they are fine, but as soon as it rains heavily and I need to brake I really need to stamp the pedal down a couple of times to get anything like 100% braking power.

Any ideas what might be up?

I will probably take it into the local dealership but could do with being 'forearmed'.

Cheers

[Mazdarese]

EDLT said:

fatboy b said:

Water on the discs. My Audi does an occasional dry of the discs if the wipers are turned on by lightly putting the brakes on for me. Cars without this have what seems like seconds between applying them and for them to start working.

BMWs do the same thing, probably a few others too.

To the OP: What do you think the dealer will do about it?

None of my other cars have ever had this problem, so I don't think it's a normal build-up of moisture. I think there's either a serious drainage problem or something else maybe?

I would hope my dealer would diagnose and offer to fix. They've been very good in the past.

[Mazdarese]

dme123 said:

I'm sure the main dealer is more than capable of bending the laws of physics for you :-D

Seriously, this is not a normal build-up of water that can be explained away with physics. I've driven in heavier rain in other cars and not had anything like this.

[Mazdarese]

N Dentressangle said:

Mazdarese said:

Seriously, this is not a normal build-up of water that can be explained away with physics. I've driven in heavier rain in other cars and not had anything like this.

You need to replace at least the pads, asap.

I bought a Saab 900 a few years ago which did exactly what you describe. It was scary. Otherwise, the brakes worked fine.

I replaced the pads with new genuine items and the problem disappeared. The pads I removed looked worn, but with plenty of 'meat' left.

Never had this problem with a car before or since, but new pads cured it straight away.

HTH

Ok, thanks. I'll get a price from my local Mazda place and if it's ridiculous I'll do them myself.

If it solves the problem I'll come back and push a custard pie into the faces of people who said I was a mong and that it was physics.

[Mazdarese]

Huntsman said:

Dont drive like a tt in the rain?

You're right. Next time it rains I will slow down to 40mph. Shall I put on all my fog lights too and stay in whichever lane I was in before the downpour started?

[Mazdarese]

Huntsman said:

Mazdarese said:

You're right. Next time it rains I will slow down to 40mph. Shall I put on all my fog lights too and stay in whichever lane I was in before the downpour started?

By your own admission, 70 onto a slip road in heavy rain. Sounds like you need to take account of the prevailing conditions more to me.

Further, if you needed 100% of braking effort, as per your post, you had no extra braking available if you needed it.

No offence intended, maybe I'm just a doddery old fool and keyboard warrior too.

Nope, you just read too much into my post. I used the 70mph/heavy rain/100% braking terms perhaps to highlight that it was quite a serious issue. In reality, I was probably only doing about 50mph on the occasion I was referring to.

It has happened when I've been pootling down the road at 30mph too.

[Mazdarese]

Thanks for all the replies.

I'm not sure what pads are on the car as they were on when I got it in November last year. I've had a quote of £135 quid for a set of OEM front pads from Mazda, and an hours labour, so nigh on £200. I'd rather see what other MPS drivers recommend on the MPS forum and fit them myself, as I'm sure I can get DS2500's for half that.

The tyres currently on the car are Gerutti Again, just about fine in the dry, lethal in the wet but I don't think they'll be responsible. I have four Goodyear Eagle Asym's going on at the weekend

[Mazdarese]

Well, who would have thought? Not only do 4 x Eagle F1's completely transform the car's handling, but I'm 90% sure they've also solved the braking problem. I've done 200 miles on the new tyres though a lot of rain, and the brakes feel superb.

How does that work then? How can crap tyres affect the braking so much? Such a poor design that they were channelling water straight onto my brakes?

[Mazdarese]

HellDiver said:

Did you read my previous post at all? Scroll up, read it, there's your answer.

Sorry, no I didn't.

I'm sure I had the Gerutti DS628 on, but they don't look like they have the characteristics you suggest.