M3/XJ

Hello all,

I've gone through the existing brake threads I could find but didn't find one that really answered my question. I've got a 2000 XJ Classic with 110k. Fantastic truck, dead reliable...until now. A couple months ago, the brakes began to feel spongy. The pedal never went to the floor, but it just took noticeably more effort to depress the pedal enough to stop the car. The pedal traveled farther as well.
I took it to a shop and got (I think). They said the right rear cylinder (?) was leaking fluid, decreasing stopping power. They replaced this cylinder, and the shoes and drums on both sides (in the rear). It felt a bit better at first, but has regressed to where it was. Pedal feels very spongy, truck takes more effort than usual to stop. It's been like this for 2k miles or so. Fluid level is stable. I'm wondering if the shop fixed one problem but simply didn't bleed the brakes very well.
Ideas?

MasterShakeXJ

rear wheel cylinders is what those are. did they replace both cylinders or just both? was this a reliable shop? sounds like they didn't bleed your brakes when they worked on them, try doing it yourself with a friend to press the pedal for you. thats where i'd start.

check your front brakes too

parkerbabco

well if you have to put lots of effort into the pedal your vacuum line going to your booster might be off.. brakes probably need bleed though most likely and makes sure the bleeders are tight when you close them after your done.. they mightve bleed it and didnt completly close the bleeder

ol"blue

^^X2 When bleeding them make sure you don't let the master cylinder get low on brake fluid. Do right rear first, then left rear. If you then do the fronts, do the right front, then the left front. You always start with the wheel farthest from the master cyl. first, and end with the closest to the master cyl..

a1racer

i would run all new fluid through the system as it gets older water gets in to it. so bleed the system a few times to get the old stuff out and the new stuff in this should help if not you have other issues. i would still replace the vacume line going to the booster just in case it is a super cheap thing to do

dlundblad

Just sounds like they didnt bleed your brakes.

jd4x426

try bleeding the brakes and check to make sure the other wheel cylinder or the calipers arent leaking

BuckB91XJ

Any shop that replaces brake parts on only one side should be friggin fire bombed. EVERYBODY knows if you do shoes, pads, rotor, caliper, wheel cylinder or drum....YOU ALWAYS DO BOTH SIDES AS A SET. Both sides have the same amount of miles/abuse on them. If you have to change one rear wheel cylinder due to leaking, it'll only be another 10 minutes before the other one starts, DUH!!!!!!! I would bleed the whole system again,get a big can of fluid so you can bleed it all the way through to where you have good clean new fluid thoughout. You problem really sounds like a Master Cylinder going bad to me, though. MC or the Power Brake Booster.

M3/XJ

Thanks guys. I'll try bleeding it first.

Firestorm500

He said fluid level was stable--therefore no leaks.

Firestorm500

Spongy brakes:

Air in line(s)

Contaminated linings with grease or brake fluid.

Master cylinder going bad--fluid bypassing plunger inside (not leaking)

Cheap brake shoes/pads

M3/XJ

I took it to a shop here in Leavenworth, and told them to bleed the brakes first. They bled them and found no air in the line, but said the rear brakes were out of adjustment. They adjusted the shoes and re-bled them. The pedal feel is significantly improved, especially at highway speeds.
I thought drum brakes/shoes were self-adjusting, though. ?
They also filled up the brake fluid reservoir very high-it's not just to the full line, but almost all the way up to the cap. Is this bad?

Firestorm500

rear brakes self-adjust up to a point.

if fluid does not overflow, you're ok.

97XJtech

the adjuster cables stretch out over time and they can actually loosen the shoes.. but if they replaced all that stuff they should have done a new disk break hardware kit and that would have came in it