I have some concerns with my brakes on my '07 G35S. I started feeling that the brakes weren't biting as hard as normal about a month ago. last year, I replaced the front rotors and pads with R1 Concepts blank rotors and posi-quiet ceramic pads. 2 weeks ago, i changed the rears with the same thing (rear rotors were warped anyway).

I still had a spongy feel. I then bled the brakes. not much changed.

Currently, I feel like I need to double pump to get a somewhat decent feel. The car still stops, but feels wrong.

I took it to the dealer. They were unable to find a problem with the brake system (maybe it's all in my head). But the loaner G25X has immediate bite! Almost breaks my neck in comparison, much like when I bought my G.

Any thoughts on this? Should I go try a different pad? Dealer recommended that I flush the entire brake system as well (probably due anyway).

Thanks for any input!

 

usually flushing the fluid does the trick along with a fresh pair of pads, and since i also have posi ceramic pads i can tell you that the bite is pretty nice and will stop as well as any other pads.

With that said, i would say to re-check your fluid and the brake system for any air left in the system which should be the culprit, however if u truly have bled the system properly leaving no air within the system then go with SS brake lines which does help stiffen things up.

 

I guess since they have my car, I'll probably go ahead and have them flush it then. I'd do it myself, but i'm feelin a bit lazy.

I might go ahead and order an OEM set for the front just to see if there's any difference after the flush, too.

 

A few things come to mind. (assuming the lines were correctly bled)

1) Old, tired, brake fluid.
2) Grease, oil, or severe glazing on the pads/rotors.
3) A flaw (bubble) forming in the rubber brake lines.

 

also if the rotors are in good shape then performing the pad break-in process again can only help

 

1) possibly. bought the car as an infiniti certified pre-owned in 09. they SHOULD have replaced all fluids. I certainly have not...

2) not likely. I'm very careful during install. Unless something got on them while driving, there shouldn't be a problem.

3) suppose that's possible. might look into some stainless steel lines...

 

rears are brand new.

fronts are 1 year old and "seem" to be fine (i.e. no warping, etc...)

The posi-quiets don't really have a pad break-in as they are pre-scorched. However, I always do it. Guess I could try again.

 

I also just did all this a few weeks ago,, >new R1 prem. blanks, front and rear, and hawk hps pads< all went well, but we had some trouble getting all the air out of system, also flushed out entire system with Ate Blue brake fluid, i actually had to bed the new components in with air in the system,,, funny thing is after a few miles, and by the time i got home (30 ) miles pedal was where it should be,,, now, have another issue,,, with driver side rear caliper sticking, waiting for new caliper to arrive,, still don't know how i got air in system,, and def. don't know how it got out by itself.....

 

i'm hoping it's all just air in the system too! Guess I'll find out tomorrow...

 

This is a very common issue with the G, and sadly my Altima sedan I had.

I think it's a Nissan issue and maybe can't be ironed out with bleeding. I bled my brake with a powerbleeder and put on new pads all around.

 

I've always used the Powerbleeder with mine as well, and I've never had any issues with trapped air in the G. On other cars (BMW), I HAVE seen where air gets into the ABS system and then can be a bear to get out. The dealer has no problem there since they can operate the ABS solenoids and pumps with their diag equipment. What I've done on the cheap was to initially bleed the brakes as well as possible, then go out and mash the pedal a few times. This invoked ABS and cycled any air through the ABS system and out into the regular lines, where I then was able to re-bleed it and get back to 100% once again.

 

so I've had the car back for a day.

They flushed and filled the brake system with synthetic fluid, etc...

The brakes do feel "better", but in comparison with the G25X loaner I had, the pedal still moves further and requires a bit more effort. The G25 had a ton more "bite". However, braking is overall quite good.... just have to push too far, IMO.

I may try getting some OEM pads for the fronts to see if that gives me more bite over the posi-quiets.

Dealer still stated there was nothing wrong. perhaps a stop by a brake shop for an inspection might give me some different "opinions", however biased they might be

 

The brake pads have a lot to do with this. It could be that the brake pads are glazed like someone already stated, or it's just the way those brake pads are. I've always learned to sand down the brake pads just a bit to get rid of whatever coating is on it left from production to help avoid these issues. Good brake pads can make a world of a difference. In a worse case scenario that you should never encounter, there could be grease on the rotor.

If you are set on keeping those brake pads now and in the future, you can always try metal brake lines to give you a better brake pedal feel. I personally do not feel that brake fluid matters too much on a daily driver as long as it's fresh and not too old.

I've never been a huge fan of Hawk pads. They aren't low on my list but I've had better all around experiences with other brake pads like Project Mu, etc...
And for those of you looking for a good, cheap brake pad, Akebonos aren't that good either.

 

oem pads have very good bite. Going back to them should make a difference. I have used different pad types on my Z but the OEM ones still feel the best for daily driving and in most temperature ranges, excluding high heat/track use

 

changing the fluid helped a bit, but I agree that in general, unless there is air in the lines, it shouldn't have been the biggest factor.

I think I'll try the SS lines AND get a set of OEM pads. While i'm comfortable driving on what I have now, I'd rather spend a bit more and make them better.

I liked the hawks for AutoX, but for daily, I did not like them.