Nissan 370Z Forum  

Intense Brake Judder…that Disappears Under Threshold Braking

I just wanted to post this thread to help anyone else trying to diagnose the particular brake judder issue I was having. Here were my symptoms: 1) No braking issue

Go Back   Nissan 370Z Forum > Nissan 370Z Tech Area > Track / Autocross / Drifting / Dragstrip


Like Tree2Likes
  • 2 Post By ResIpsa

Reply
 
LinkBack Thread Tools Display Modes
Old 07-02-2015, 02:16 PM   #1 (permalink)
Track Member
 
ResIpsa's Avatar
 
Join Date: Apr 2009
Location: Virginia
Posts: 564
Drives: 09 RACING HEN
Rep Power: 337
ResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond repute
Default Intense Brake Judder…that Disappears Under Threshold Braking

I just wanted to post this thread to help anyone else trying to diagnose the particular brake judder issue I was having. Here were my symptoms:

1) No braking issue (judder) at the track with track pads at about 75% pad remaining.
2) As the weekend progressed I started to notice a slight judder under braking.
3) The judder got progressively worse after each subsequent track session. The judder was more pronounced under trail braking.
4) By the end of the weekend, when my pads were <25% remaining the judder got so bad the car felt dangerous and trail braking was all but impossible.

Now the key symptom.

5) If I just kept the car in a straight line and applied 100% braking force (aka threshold braking) the judder would disappear and my braking would be smooth. However, when I backed off to anything less than threshold braking the intense judder would reappear.

Rather than go into the multitude of possible fixes I will let you know what worked for me. I suspected that the issue had something to do with the pistons when they were overly extended. Maybe sticking, maybe the years of track use has slightly rounded out the caliper seats, who knows.

My fix was to take an old set of street pads and use a hammer and chisel to remove all the remaining pad material creating a backing plate. I then cleaned the caliper and pistons best I could and lubricated the pistons with plenty of brake fluid. After compressing the pistons I inserted the backing plates behind my badly worn pads and voila! The judder is completely gone!

So the problem did have something to do with the over extension of my caliper pistons. If you ever run into this problem I hope this helps.
P's_Z and AntiVenom like this.
__________________
The Reed Law Firm; Michael Fasano VA Attorney and Counselor at Law: A Virginia Traffic, Criminal, and Family Lawyer.https://reedlawva.com/
ResIpsa is offline   Reply With Quote
Old 07-03-2015, 06:21 PM   #2 (permalink)
The370Z.com Sponsor
 
Mike's Avatar
 
Join Date: Jun 2009
Location: Loganville, GA
Posts: 5,944
Drives: 370z
Rep Power: 2185
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

interesting! probably not pad deposits afterall as we all thought. Makes total sense.

Wish you figured this out 4 years ago, would have saved me the $7000 I spent on the stoptechs because I didn't want to deal with it!
__________________
NISSAN: 75 280Z / 86 300ZX GLL /87 Sentra SE / 03 350Z / 23 Z
Porsche: 93 968 / 23 Macan GTS / 93 968
Mike is offline   Reply With Quote
Old 07-04-2015, 07:09 AM   #3 (permalink)
Track Member
 
ResIpsa's Avatar
 
Join Date: Apr 2009
Location: Virginia
Posts: 564
Drives: 09 RACING HEN
Rep Power: 337
ResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond reputeResIpsa has a reputation beyond repute
Default

I am glad at least someone found this helpful. Who knows, maybe this is a problem with our sport brakes.

All I know is that there is nothing worse than trying to track down a mysterious source of brake judder.
__________________
The Reed Law Firm; Michael Fasano VA Attorney and Counselor at Law: A Virginia Traffic, Criminal, and Family Lawyer.https://reedlawva.com/
ResIpsa is offline   Reply With Quote
Old 07-04-2015, 05:35 PM   #4 (permalink)
Ronin Samurai - Assassin
 
Rusty's Avatar
 
Join Date: Dec 2011
Location: Fayettenam,Pennsyltucky
Age: 68
Posts: 34,812
Drives: 2011 Nismo GM 6M
Rep Power: 2684436
Rusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond reputeRusty has a reputation beyond repute
Unhappy

Interesting is right. From reading the above. It seems when the pads are worn down to <25%. There is not enough brake piston in the bore. Allowing the pistons to cockk in the bore? So, solution is to get longer caliper brake pistons. Next question. Who makes them?
__________________

浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html
Rusty is offline   Reply With Quote
Old 07-05-2015, 02:51 AM   #5 (permalink)
A True Z Fanatic
 
Join Date: Dec 2009
Location: 03350 Australia
Posts: 1,502
Drives: 09 Nissan 370Z M6
Rep Power: 29907
BGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond reputeBGTV8 has a reputation beyond repute
Default

I work on minimum pad thickness including backing plate of 12mm and with 5mm backing plates this is 7mm of pad material left which is a key heat insulation contributor

I work on around 13mm of effective pad material to use before replacing pads.
BGTV8 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
370Z For Sale 40th Anniversary ~ Get it before it disappears! herZ and hiZ 370Z For Sale 8 02-19-2013 09:26 AM
40th Anniversary ~ Get it before it disappears! herZ and hiZ 40th Anniversary 370Z 11 02-01-2013 08:05 PM
Fix brake vibration by braking really hard to remove pad deposits? wdkwang Brakes & Suspension 60 06-22-2012 08:50 AM
Anyone know whats up with Intense??? Carbon Fiber Element Exterior & Interior 2 10-27-2011 11:58 PM


All times are GMT -5. The time now is 01:58 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2