So when I bought the car about 10 months back and got it inspected, they had said the brakes were at 90% and they felt extremely weak.
Since then I haven't touched them and I'm getting pretty tired of it after I drove my parents new 328i all last week and had the response and power of its brakes.
They just feel really crummy and if my foot is not all the way to the floor my car won't stop rolling (automatic).
Any suggestions?

 

you might want to make sure the car has OEM pads....

does it have a lot of black brake dust? if so, i can't help you there.. you probably have semi-metallic or OEM pads which is probably best for this car.

if the dust is not much or yellow/gold-ish.. then you probably have ceramic pads/ non-OEM pads which gives up a lot of brake performance.

Personally, I would change the pads back to OEM and bleed the brakes (i am also assuming the rotors are good.) .. this will cost what? $60 for pads and $20 for fluid if you DIY..

If after this you still don't like your brakes.. I don't know what to tell ya.

BMW's have great brakes, it's VERY balanced.. but the G35 has one of the better OEM brakes in terms of stopping distance..

 

Regardless of what brand/type brake pads you have your cars going to stop and far better than you describe! Every neighborhood has a independent brake/alignment shop, all they do in brakes and suspension work...find yours! If you don't have one ask your favorite parts store who they recommend. You have brake issues going to the dealership or tire stores isn't the best idea, they're just expensive parts swappers...Gary

 

Have your tried pumping them to see if they build better pressure? Could be air in the lines, or even dirt in the lines causing poor fluid movement. I'd give the system a good bleeding and see if that takes care of it.

 

The pads would be worn to metal if the pedal reached the floor and the brakes were bled correctly. Go buy a bleeder kit and go bleed you brakes.

 

There is a hose going from the upper plenum into the battery compartment. Disconnect that and try blowing through it on both ends. It should only allow air in one direction if you feel air in both directions then the check valve inside is bad.

Check your brake booster:

Operating Check

With the engine stopped, change the vacuum to the atmospheric pressure by depressing brake pedal several times. Then with brake pedal fully depressed, start engine and when the vacuum pressure reaches the standard, make sure that the clearance between brake pedal and floor panel decreases.

CAUTION: Depressing pedal interval is approximately 5 seconds.

Airtight Check

Run engine at idle for approximately 1 minute, and stop it after applying vacuum to booster. Depress brake pedal normally to change the vacuum to the atmospheric pressure. Make sure that distance between brake pedal and floor panel gradually increases.

Depress brake pedal while engine is running, and stop engine with pedal depressed. The pedal stroke should not change after holding pedal down for 30 seconds.

If all those check out good next step would be check the fluid make sure there it's between MIN/MAX. If it hasn't been changed in a while you can DIY it, I bought a Motive Power Bleeder makes it an easy job.

 

Thanks for all the replies guys.
So as joedaddy brought up the brake dust, mine doesn't show until it rains or the sprinklers hit them and after that it shows yellow brake dust. Thats not oem right?
I'm gonna order oem brake pads and maybe bleed the brakes if they still aren't acting right.

 

sounds like yours is not OEM.. OEM pads have a very noticeable black brake dust like most BMW's.

i've been using OEM pads for 10 years before I switched to ceramic last year since everyone was complimenting them.

Well, the performance drop is very noticeable, especially in the cold weather. I am NEVER going to recommend ceramic to anyone unless it came OEM with the car.

Also, I would definitely go ahead and bleed the brakes while doing the brake pad service.. looks like your fluid is "spent."

good luck.

 

Having been a member of Driver since '05 I don't recall anyone complimenting ceramic pads! If they did they haven't driven very far or often and you're listening to the wrong members. Even www.thetirerack.com doesn't rate ceramic pads as high as non ceramic brake pads, they do a lot of testing!
Gary

 

I think you have some sort of mechanical issue here beyond what brand pads you have on you car. For example, gold brake dust is usually rust, which means your pads have worn down to nothing and now your metal backing plates are making contact.


Here's pretty much what you need to do. Get the car on jackstands and pull all 4 wheels off and grab some tools.

1st off, inspect all the pads and rotors. Both sides of the rotors and both pads through the caliper. Verify all the rotors are smooth and not grooved and all the pads are full of material and WEAR IS EVEN. That's a big one because G35 rear calipers are very prone to sticking and will wear the pad off one pad down to backing plate VERY quickly.

Bleed the brakes. Brake fluid should be bled yearly, but nobody ever does. On a 10 year old car, the fluid could be so saturated with moisture that a boil-over or two could create a very bad feeling pedal.


You also didn't say what model G35 you have, so can't comment on the particular braking system of the car.

 

I have the Akebono ACT Pro ceremics on my car and have had them for over 50K miles. No different in terms of noise, dust, brake feel and rotor wear than the 2 sets of OEM pads I ran the first 100K miles on my car. I'd buy them again.

 

search for "proact"
prepare to have your mind-blown.

 

Check your caliper slide pins are doing their job, if not clean and grease them..