Front brake locks up - JeepForum.com
 
LinkBack Thread Tools
post #1 of 9 Old 12-10-2019, 02:25 PM Thread Starter
Hamid
Registered User
 
Hamid's Avatar
2000 XJ Cherokee 
 
Join Date: Jul 2008
Location: Jeddah
Posts: 308
Front brake locks up

Hi everyone:


After I installed new rotors, new pad, and new caliper piston, the front brakes jammed. I bled the system, no help.
What could be the problem since everything almost new.


*****************
2000 Jeep Cherokee Classic. Built for export
432K Kilos.
Hamid is offline  
Sponsored Links
Advertisement
 
post #2 of 9 Old 12-10-2019, 02:43 PM
mauser1891
Registered User
1997 ZJ 
 
Join Date: Apr 2014
Location: LaConner
Posts: 18
Disc brake hang on knuckle... ('89 XJ)

Hello Hamid,

I suggest inspecting the knuckle for wear. I am in the process of replacing the one on my girlfriends '89 Pioneer. I had purchased drums, rotors and all the rest of the parts needed to do the core portion of the brake system at the wheels. Over time usage wears the knuckle, thus the front brakes can no longer move as intended. It's that noticeable at first, but after closer inspection you will see the issue.
I am considering new parts as we might keep this build. NAPA is the only company that I have seen thus far that has both left (NPS 78541) and right (NPS 78542) knuckles. Keeping in mind that one could buy a axle from another vehicle, but it may suffer the same issue for the combined price. Therefor I'd suggest closely inspect anything you might consider acquiring that is used.
NAPA knuckles

Thank You,
mauser1891

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
mauser1891 is offline  
post #3 of 9 Old 12-10-2019, 02:49 PM Thread Starter
Hamid
Registered User
 
Hamid's Avatar
2000 XJ Cherokee 
 
Join Date: Jul 2008
Location: Jeddah
Posts: 308
Thanks Mauser, did you mean the hub.

*****************
2000 Jeep Cherokee Classic. Built for export
432K Kilos.
Hamid is offline  
 
post #4 of 9 Old 12-10-2019, 03:20 PM
mauser1891
Registered User
1997 ZJ 
 
Join Date: Apr 2014
Location: LaConner
Posts: 18
Disc brake hang up, alternative knuckles...

Hello Hamid,

The hub is bolted to the knuckle. Hub is the bearing assembly. While the brakes are also bolted to the knuckle. Knuckle is a part of the steering|suspension.
I was doing a parts look up on a different website and the same MOPAR part numbers are the very same between a '97 ZJ and the '89 XJ. Which makes sense as both are the same front axles. As we know that Jeep started making the ZJ's after the ZJ production. As it would be logical to reuse the same parts in many cases than to retool a factory line.

Example of the steering knuckle here.
I am considering these at OMIX-ADA

Thank You,
mauser1891

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by mauser1891; 12-10-2019 at 03:26 PM. Reason: update
mauser1891 is offline  
post #5 of 9 Old 12-10-2019, 05:26 PM
car6car
Registered User
 
Join Date: Apr 2019
Posts: 117
Bad brake hoses. Old. They are falling apart inside, clogging fluid flow back.
car6car is offline  
post #6 of 9 Old 12-10-2019, 06:09 PM
CJ7-Tim
Real Jeeps have dents
 
CJ7-Tim's Avatar
2000 XJ Cherokee 
 
Join Date: Apr 2002
Location: out in the garage - Minneapolis
Posts: 27,749
1) Check for wear on the brake pad sliding surfaces of the steering knuckle. Entire surface, both upper suface and lower surface, should be even and smooth. See picture. Repair any worn areas by filling with welding filler metal and grinding smooth.

2) Replace both the rubber brake hoses to the calipers. Old hoses can break down inside and crate a blockage to return flow of brake fluid.

.

.

A recent Gallup public opinion poll shows the NRA, at 58% approval, has a higher approval rating than either Hillary Clinton or Barack Obama.

Progressive Liberalism: Bringing you new Healthcare ideas so wonderful, they have to include mandatory participation ...

Originally Posted by Ronald W. Reagan: Government is not the solution to our problems; Government is the problem.
CJ7-Tim is offline  
post #7 of 9 Old 12-11-2019, 04:42 AM
MaskedMallard
Registered User
2001 XJ Cherokee 
 
Join Date: May 2009
Location: MN
Posts: 762
Garage
Xj

From 1999 - 2000, the front axle changed. It's possible that you now have a mix of 1999 & 2000 front axle brake parts.

2001 BJC Orvis XJ Build -
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
MaskedMallard is offline  
post #8 of 9 Old 12-11-2019, 05:44 AM
CJ7-Tim
Real Jeeps have dents
 
CJ7-Tim's Avatar
2000 XJ Cherokee 
 
Join Date: Apr 2002
Location: out in the garage - Minneapolis
Posts: 27,749
The description of the symptoms is somewhat vague, but the 1999.5 cast vs. composite rotor and hub issue is a likely possibility.


Read this >> https://www.jeepforum.com/forum/f11/...e-hubs-360959/

.

A recent Gallup public opinion poll shows the NRA, at 58% approval, has a higher approval rating than either Hillary Clinton or Barack Obama.

Progressive Liberalism: Bringing you new Healthcare ideas so wonderful, they have to include mandatory participation ...

Originally Posted by Ronald W. Reagan: Government is not the solution to our problems; Government is the problem.
CJ7-Tim is offline  
post #9 of 9 Old 12-11-2019, 12:21 PM Thread Starter
Hamid
Registered User
 
Hamid's Avatar
2000 XJ Cherokee 
 
Join Date: Jul 2008
Location: Jeddah
Posts: 308
Thank you for all your info sharing, her what I found:

The rotor was touching the back plate, and when the wheel lugs were tightened, it put great pressure on the rotor made very hard to move. As a quick solution, I put washers on the wheel stud to separate the rotor from the back plate. It did work, the brakes is working now normally.

*****************
2000 Jeep Cherokee Classic. Built for export
432K Kilos.
Hamid is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may 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 Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome