Brake pedal to floor intermittently - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Grand Cherokee & Commander Forums > WJ Grand Cherokee Forum > Brake pedal to floor intermittently

Poison Spyder DeFenders™ - "Tubeless" Jeep FendeAll Bilstein shocks & struts - Lowest Prices Ever and Santa Kolak Announces: Kolak Exhaust 20% Off Sale!

Reply
Unread 09-18-2013, 08:41 PM   #1
BigAl63
Registered User
2000 WJ 
 
Join Date: Jan 2013
Location: Central, La.
Posts: 106
Brake pedal to floor intermittently

The last couple of days, the brake pedal has been normal on stops after start up. After a little while of stop and go driving, the pedal begins going almost to the floor. Still finally get to brakes, but the pedal is almost to the floor. Then, randomly, it returns to normal. Brakes catch at the normal position. I'm thinking master cylinder, but has anyone had this happen and what was the prob? It's full of brake fluid. 99 Laredo, 4.7 if it matters. Thanks in advance for any help.

__________________
2" BB, 1.25" wheel spacers
BigAl63 is offline   Reply With Quote Quick reply to this message
Unread 09-18-2013, 08:54 PM   #2
bradywgn71
Web Wheeler
 
bradywgn71's Avatar
2002 WJ 
 
Join Date: Apr 2011
Location: Tucson, Arizona
Posts: 1,052
That's the sign of a bad master cylinder. Does the brake pedal get firmer if you pump the brakes?
__________________
2002 WJ Overland - 4.7HO - 231tc - 6" Clayton - 285/75-16 Cooper STT - ProComp 5129 wheels - Kevin's Offroad Belly Skid and Rock Sliders - JKS Track Bar and Disconnects - ProtoFab bumpers
bradywgn71 is offline   Reply With Quote Quick reply to this message
Unread 09-18-2013, 08:57 PM   #3
BigAl63
Registered User
2000 WJ 
 
Join Date: Jan 2013
Location: Central, La.
Posts: 106
No it does not. It just keeps going to the floor. Then out of the blue, it returns to normal. Pumping while I'm stopped or rolling does not help.
__________________
2" BB, 1.25" wheel spacers
BigAl63 is offline   Reply With Quote Quick reply to this message
Unread 09-18-2013, 09:18 PM   #4
Merc1973
Registered User
2002 WJ 
 
Join Date: Jun 2008
Location: Sykesville, MD
Posts: 1,795
Quote:
Originally Posted by bradywgn71 View Post
that's the sign of a bad master cylinder. Does the brake pedal get firmer if you pump the brakes?
+1
__________________
2002 WJ Ltd. 4.7 V8, QuadraDrive
1973 Mercury Cougar Xr7 convertible 351CJ, C6, 9" rear
1970 Kaiser-Jeep M35A2 W/OW 6x6 Multifuel D-Turbo.


ΜΟΛΩΝ ΛΑΒΕ!
Merc1973 is offline   Reply With Quote Quick reply to this message
Unread 09-19-2013, 01:18 AM   #5
silentbob21
Registered User
2004 WJ 
 
Join Date: Jan 2007
Location: San Diego, California
Posts: 713
does seem like one of two things... bad master cylinder or some weird case of air in the lines that sometimes fixes itself hah... id go with #1
__________________
2004 WJ SE 4.0L I6, NV242, IRO 6.5 LAs D44a Spartan locked, 4.88s, BFG KM2s 35/12.5/15


silentbob21 is offline   Reply With Quote Quick reply to this message
Unread 09-19-2013, 06:33 AM   #6
BigAl63
Registered User
2000 WJ 
 
Join Date: Jan 2013
Location: Central, La.
Posts: 106
Thanks guys. I was thinking master cylinder too. Just looking for some confirmation.
__________________
2" BB, 1.25" wheel spacers
BigAl63 is offline   Reply With Quote Quick reply to this message
Unread 09-19-2013, 10:50 AM   #7
nickblack
Registered User
1999 WJ 
 
Join Date: Dec 2010
Location: bridgewater, nj
Posts: 739
Master cylinder. Fix it quick because soon it won't come back up at all.
nickblack is offline   Reply With Quote Quick reply to this message
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.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools






Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.