twinz33

Went to the grocery store today... Go in, come out.. Hop in the Jeep and drive off, come to a stop sign and push the brake pedal and it goes all the way to the floor.. I have no brakes and heading into the middle of the road!! Luckily nobody was coming in either direction... No accident happened... Started to pull over and pumped the brakes to stop and with each pump they came back to life. Turned off the jeep and checked the lines, no leaks or anything out of the usual I can see..

Note my jeep has the UD60's front and rear with around 11k miles on them... Ive never had this happen before or anything close.. Im at a loss..

My only guess is air in the lines worked there way through after all this time.. Or, master cylinder took a dump?? When I added the new axles I changed out the master cylinder with one from raybestos so I wouldn't think thats the case.

Any thoughts, opinions, similar cases this has happened to anyone?

richlortz

With the jeep off push on the brake pedal with even pressure and see if the pedal goes to the floor. Try that a couple of times. If it does needs a master cylinder.

twinz33

Just went and tried that. First push went about half way down, second push was less around 1/4 of the way down, third about the same as the second push

D_engel

Could've been air trapped in the abs that finally worked its way out

Slowpony46

Look over everything really well for leaks and signs of bulging brake hoses or anything unusual. If nothing appears wrong, bleed the brakes because like others said it could be air. If that doesn't do it you need a master cylinder. Your symptoms are conducive to air or a master. Just because you recently changed it doesn't mean it's good, and typically raybestos stuff is the same as any other Chinese reman so a defective one wouldn't shock me.

2climbbig

That happened to me while off roading. Then it happened again about a month later. It was my master cylinder. I replaced it am no more problems

Extremneon

Op did you get this sorted out?

How are your brakes with the Raybestos and UD60's?

What part numbers did you use and are you an auto or manual?

I order the Mopar master and reservoir and it seems to be on backorder, so I am curious of maybe alternate route with my UD60's for helping stop the one ton brakes.

Thanks,
Robert