Brakes don't stop well in rain...problem or normal?

Seems like it's a 330 only issue. My old 330 did it really badly until I switched to drilled rotors. M3 doesn't exhibit this behavior in the slightest, even though front rotors are the same diameter and rears are bigger.

You can add me to this list also. Previously drove a '00 323 which had reasonably good brakes both wet and dry. Just bought the '04 330xi and thought "wow" great brakes (dry). Very surprised to find driving in the rain today I had a second or so of very reduced braking force as well as significant pull to left. Second application of brakes seemed normal. My car was supposedly serviced at a dealer about 30k ago with new pads/rotors so I'll assume BMW OEM parts for now.

I'm thankful for this website and all the info!

Add me to the list - reduced braking force and pulls to the right under braking in wet conditions. Did anyone find a solution to this problem? Replacing with new OEM rotors?

I think I can say that I solved this problem with a fair level of confidence.

My shop replaced the rear pads at 100k because they were almost gone, but not the rotors. I still had the wet braking delay. Afterwards, I noticed that the rotors had some rust scarring towards the outer half which meant the pads were not making proper contact.

I then read all about brake pad bedding and (hopefully) I did that properly by making approximately 8 hard stops from 60 - 25 mph. I have yet to experience that scary delay in the hardest of rains now . . .

I'm 100% OEM, brand new tires and same problem, but only in heavy rain. I too suspect the cooling ducts.

BMW has addressed it for newer models:

http://www.bmw.com/com/en/newvehicle.../dsc_more.html

Originally Posted by iansanderson

I'm 100% OEM, brand new tires and same problem, but only in heavy rain. I too suspect the cooling ducts.

BMW has addressed it for newer models:

http://www.bmw.com/com/en/newvehicle.../dsc_more.html

Mercs have similar thing too by gently riding the brakes to dry the rotors.

Originally Posted by iansanderson

I'm 100% OEM, brand new tires and same problem, but only in heavy rain. I too suspect the cooling ducts.

BMW has addressed it for newer models:

http://www.bmw.com/com/en/newvehicle.../dsc_more.html

If its a cooling duct issue, M3 should do it too then right? Even when I had blank rotors, these brakes worked much better than my 330's

I can't really think of anything else though. There isn't anything about the 330 brakes that screams design flaw

I have a 04 325i sedan oem pads and rotors.. I think this might be caused on the 330 more because of wheel design. I never had this problem with my oem wheels.. When I installed my vmr v710 wheels which expose much more of the rotors I started having this problem. It does not happen when driving alone on the highway or on single lane roads but when driving beside or behind other cars I think my open wheels are letting an excess of water in.
It is definitely scary.. When I push the pedal it doesn't seem to depress as far as it should very hard to push but a couple pumps and the brakes are dry braking like a champ. Dry braking is perfect.. Tires are new.
Just an idea I had what do you all think?

Sent from my GT-P1010 using Bimmer App

So I'm not reading 5 pages of posts were perople are guessing at what is cuasing this.

If you have stock rotors and pads, the pad will naturlly surf a wet rotor until enuff heat friction has dried the pad off for the pad to begin to bite in the rotor.

Simple - This happens in ALL disk brake cars and ususally worse in drum brakes.

I used gas slotted rotors and unlike drilled rotors the gas ducted rotors sweep the water off the surface of the rotor extrememly fast.

I know the OP is from Washington State, I chose the gas slotted rotors for quick clear off because I also live in Washington state. It simply works with a lot of rain!!!!

Get the Continental DWS all season tire, (cheap with Exremely highy ratings. The gas slotted rotors and flush the brake system. You won't be disapointed in your brakes response.

You will however begin to notice how others brake behind you as they're coming up on you and They probably can't stop as fast as you can. Nice feeling actually.

I've never experienced this. Instant brake response in all conditions for me. Maybe I'm just lucky?

Never had any issue either...stock wheels, pads (textars), and blanks. I stop quickly. But, also, I almost always use my brakes firmly when I use them. So many here seem to get 'warped' rotors, I think that many are getting deposits built up on their rotors because they're both too easy on the brakes and then, maybe, after stopping when the rotors are hot, they'll leave the pads sitting on the rotors.

In an automatic, this seems more likely. Often when I'm stopped, I'll release the brake, or on an incline, will just release it and let the wheel move a bit so pad doesn't rest on one place too long.

Use your brakes harder when you use them.

I'm now having an issue where in the rain if I brake, the car pulls HARD to the right. This is after getting brand new OEM front rotors and pads, and rear pads. It's pretty scary.

Originally Posted by OUTATIME

I'm now having an issue where in the rain if I brake, the car pulls HARD to the right. This is after getting brand new OEM front rotors and pads, and rear pads. It's pretty scary.

That's good...problems with brakes should be scary.

Did you do this yourself or have someone else install them? If the latter, take it back right away.

If this is immediately after getting them, then I bet they're not bedded, but it could be that a caliper is seizing. When you can, drive about 10 mins on the highway and pull over without using the brakes. As soon as you can, touch your finger quickly to the rotors and see if one is hotter than the others. It will be on the side opposite of the one you're pulling to, either front or back.

If the caliper is sticking it would be much hotter on that rotor and the brakes wouldn't work as well as on the cold side. That is, if the brake job was just done.

Inspect the work done...make sure the wheel bolts are tight and the caliper carriers too.

Read up on bedding the brakes, and follow the directions carefully...after you've inspected things...and be careful when you do it...you'll look drunk to a cop.

I've read of a lot of problems with brakes lagging in the rain but I've never experienced this with my blank rotors. My brakes seem to stop as sharp in the rain as in the dry.

In short, we fixed it. I'm not clear on what went wrong - the shop told me that one of the brake rotors were not "mounted correctly on the hub" due to a rusty hub . . . they cleaned it and remounted (for free) and it seems to stop well in the rain now. I hadn't bed the pads yet - I can't find an opportunity (enough space/time). I believe they machined the rotors as well so I'll re-bed the pads and see what happens.