Sorry for the semi long, and possibly hard to read post. but.............

I have a 2003 Nissan 350Z Touring, and I been having a slight (might not turn out so slight) brake problem. About 6-9months ago I had my brake fluid replaced and every since then my brakes have felt, weird. They start off in the mourning fine, but after few minutes of driving, the brakes stop biting as good. The braking performance gets worse. Then recently I replaced my brake pads and rotors and ALL 4 now either smell like smoke or are smoking after I get out of the car. So I figured maybe the pads I bought weren’t up to par, so I returned them (bendix pads) and bought some higher performance pads and rotors, and they still SMOKE.


So the problems with my brakes so far seem to be:

1. Poor braking performance after few minutes of driving (has happened for at least 6months)

2. Brakes either SMOKE or smell like smoke after I drive (has been happening ATLEAST for 1 month, but could have been happening longer, maybe I just didn’t pay attention )


So I started to think about it, and the only thing I could think of was my calipers on my brakes were sticking (would heat up pads so high that it would hurt braking performance and cause smoking) but the likeliness of all 4 calipers going bad at once is, well, rare I would think. Then I thought about it, is this is a typical sign of a faulty MASTER CYLINDER?

If so, how much does it typically cost to get Master Cylinder Replaced???? Should I have it replaced at dealership? Or should I have dealership inspect my brakes and have them find the problem (Ill bet $5 they say the problem is my Project MU NS brake pads). How hard is it to replace the Master Cylinder?
Since my car is out of warranty, can any respectable mechanic replace a Master Cylinder and not waste money at a dealership?

OR could it be something else? I know it’s hard to diagnose something like this over the internet , but before I take my car to the dealership here (rip-off probably) I would like some opinions on what it could be.


Thanks for any advice

 

I always suspect the thing that you last changed....in this case the brake fluid.

It is cheap.....buy some new good quality fluid and bleed the entire brake system.

 

you think bad brake fluid can cause my brakes smoking/burning tho?

 

Did you bed in your new pads and rotors? If done right bedding in new pads to rotors can cause a burning smell. Do you hear any squealing?

 

after warmed up, not squealing. yes i bedded them in correctly. I am not only smelling it, but i see SMOKE coming from the rear sometimes.

 

You have a leak then.

What fluid do you have ?

 

im not sure of the brand name of the fluid, i know its DOT 3 tho.....

 

Have you checked for leaks at the rear brakes ?

 

When i was replacing the pads and rotors i didnt notice anything. Everything looked fine, I guess i could inspect it again. If there was a leak it would have to be VERY small.

but could a leak cause all 4 brakes to have a burning smell and/or smoke?

 

You can't find a leak before you try the brakes. 1,200 psi will make it pretty obvious.

Did the fluid reservoir empty itself while bleeding? You could have air in the master if it did.

 

i doubt theres AIR in the system because the pedal isnt soft like that (i have had brakes were there was air in the system).... I will check for leaks tomorrow,

 

I am just curious if theres a possibility of it being anything big like a master cylinder or something, or if its most likely something like a leak?????

 

Who replaced the brake fluid, you or a shop? Are you absolutely sure they didn't use a DOT 5 synthetic? Synthetics could eat through the piston seals and cause a leak into the brakes/calipers/etc.

Did some fluid or grease get on the rotors? That would certainly emit a burning smell. Get some brake cleaner spray and wash/wipe down both surfaces of the rotors.

Look at the pad faces and make sure they're not getting soaked in grease or oil.

If there was a problem with the master cyl and the brakes were dragging somehow, after driving it for a while, the rotors would have to be very hot. Do you notice that they are extremely hot? If you can find access to a pyrometer, you could measure them after a reasonable driving distance and see if they are smoking and how hot they are. I've come off the road course and read my rotor temps at around 600º with no smoke or burning smell just for comparison.


If you had a large leak, it seems like you'd notice the level in the reservoir dropping. It doesn't seem likely that all four calipers/rotors are being leaked on though.

What brand of pads are you using now? Ceramic, metallic?

 

If the rotors were sticking and you continued to drive on them for a month with any extended trips you would have likely warped at least one of them, and would feel it as a rotational thump or hum at a minimum.

My guess is that you have a leak. Dave is right on the money about the true synthetic causing seal failure, double check the type of fluid you added.

 

Local shop did the fluid, im positive (99%) that they used DOT 3......

I replaced the pads and rotors (easy and semi clean job, reason i didnt want to mess with the fluid)

The brake pads are PROJECT MU NS, rotors are centric in the rear, raybestos or bendix front, cant remember. (next time im getting centric tho)

rotors are clean. that was my first thought that some grease got on them. level in the reservoir is stable, never seen it drop.

I know rotors typically are hot after driving around, but my ROTORS do seem EXTREMELY hot compared.

 

does the synthetic fluid have a certain color? or does it look just like typical yellow brake fluid? just out of curiousity. The stuff in my resovoir tank is typical yellow color~

 

I dont see how all four wheels could be smoking due to a fluid leak.

Only that I see that could cause something like that would be if all the pads were binding on the rotors without the brakes being applied. It seems very unlikely though.

 

well i should say this (if i havent already :-\). The fronts have actually never smoked, they only smell like they are burning. It is the rears that have smoked.

 

All brake fluids are synthetic.

BUt yes, Dot 5 would have been a no go.

 

called them up and found out they used Valvoline Brake Fluid: Dot 3 & 4; Synpower...