cambam91

Hey there! So I have a 98 XJ and I just changed out the pads. shoes and wheel brake cylinders. When I finished bleeding the lines I noticed that now when I turn the car on and press on the brake pedal it makes a whooshing noise. My braking isnt affected either. Anyone got any experience with this?

EEVEE

If its an air noise thats normal lol. Can we get a video by chance to make sure?

cambam91

sure can! the video starts with the car on and then you can hear when i turn it off and the noise goes away in a few pumps.

Cherokee_of_Tennessee

I would bet my money that your brake booster is on its way out. I just swapped mine. Before I swapped it, I had more of a rubber squeaking sound instead of a woosh.

cambam91

If the gasket around the input shaft and atmospheric vacuum port has tears in it, would that potentially be causing the noise? Im thinking when i was pumping the brake after changing them it got torn and thats why it only started doing it now.

Cherokee_of_Tennessee

Not sure, I can only speak from experience as to what happened to mine. I just posted a detailed explanation as to what happened on my mine if you want to take a look at it. May not be the same issue.

cambam91

yeah after reading that it sounds like either way that if i replace the brake booster the problem and many other small things that arent problems yet will be fixed. Thanks for the write up.

EEVEE

tbh that sounds normal. Mine sounds exactly the same. I would get a video butttt pouring rain and sticky brakes i cant lol.

bad_idea

That is a blown seal on the booster. Does the jeep idle rough? That is a vacuum leak from the booster. Push the pedal in a bit, does the 'whoosh' sound continue while the pedal is pressed? The booster uses engine vacuum to increase the force on the master cylinder push rod. If it is leaking out into the interior, then it's not pushing that force onto the master cylinder push rod. That seal will get much worse to the point you will hear that sound the entire time the vehicle is running.

It will not lead to complete failure of the brakes. It will lead to the brakes being harder to press though. You should replace the booster. Its about $100 and a couple hours work. You will likely have to remove the brake lines to get the booster out. Might as well replace the master cylinder while you are in there.

EEVEE

Oh is it? i didnt know that....

cambam91

Thanks for the feedback! Looks like Ill be replacing the booster next now. Always learning!

renwa kurd

did that fixed yours? I have the same issue and when i release the brake i hear a hissing sound for some seconds

Cordless telephone

this is a 3 year old post i doubt anyone will respond.