PDA

View Full Version : car brake questions


wonky
09-17-2008, 10:08 PM
I have a Jeep Liberty with 70000 miles on it. I just got new tires and new rear brake pads today.

My front brakes, however, have never been changed and are, according to everyone I've had look at them, "Fine."

1. Isn't that a bit unusual, to replace the rear brake pads before the front ones, and to have "fine" pads after 70000 miles? I know very little about cars, but this strikes me as odd.

Something went weird with my braking, which is why I was in the shop in the first place. One of my rear brake pads, according to the dude working on my car, had "come off." The other one was quite worn.

So, next question:

2. Come off? A brake pad can just fall off? Is that just a function of wear or what? I last had my tires rotated about 10000 miles ago, and I had brake pads then!

Askance
09-18-2008, 12:41 AM
It's more than unusual, it's downright suspicious. Do you know for sure your front pads have never been replaced, in any service you've had in that time?

The front brakes usually take most of the wear as the weight of the car is borne by them as you brake. The only thing I can imagine stopping that from happening is really badly adjusted brakes, that virtually only grabbed at the back so the front ones were essentially unused. Needless to say, this is dangerous.

Magiver
09-18-2008, 01:16 AM
Your front brakes do most of the stopping. Yes, you are wise to question this. If you take your vehicle to an empty parking lot and slam on the brakes does it appear to stop well? It has me wondering if the master cylinder is ok or if you have air in the brake lines.

Asylum
09-18-2008, 01:42 AM
2. Come off? A brake pad can just fall off? Is that just a function of wear or what? I last had my tires rotated about 10000 miles ago, and I had brake pads then!
IANA mechanic, but brake pads can come off, and I had it happen to me several times on the same car. I'd ask your mechanic to look at your caliper (a part of your brake system).

Basically, your brake pad gets pressed against your tire assembly to slow and stop your car. Your brake shoe is attached to your brake pad and keeps it in place in the breaking assembly. Your car has a clamp called a caliper that pushes your brake pad and shoe against the tire assembly to increase friction facilitating the slowing and stopping of your tire and car.

The car I had had a problem with, the caliper for the rear tire wasn't letting up pressure on the brake pad when I let off the pedal, which eventually caused the brake pad to be torn off the brake shoe. The brake pad didn't go flying off into traffic, but it rattled around the brake assembly which greatly decreased its lifespan.

I have no idea if this is your situation, but I'd ask your mechanic to look into it.

gotpasswords
09-18-2008, 02:46 AM
I'd say it's time to carefully push the vehicle to a good brake shop. Not a muffler shop that also sells brake pads or a department store that sells tires, oil changes and the occasional brake pad - an actual brake shop.

Yes, brake pads can come loose. I see them now and then in the gutters around town. People pay no heed to the squeaking, which then progresses to grinding, and eventually, the pad's backing plate gets worn down so thin that it works its way out of the caliper. By this point, you obviously need new pads, plus new rotors and the caliper has also probably been damaged.

As for the front brakes being OK on the original pads after all those miles with the problems you're having in the rear, my first suspicion would be the proportioning valve is jammed and is sending almost all of the hydraulic pressure to the rear, resulting in the rears doing all of the braking, while the fronts are doing hardly any at all.

Tuckerfan
09-18-2008, 06:38 AM
Yeah, you're going to want to get this looked at very soon, like now. There's clearly something wrong if your front brakes aren't wearing faster than your rear brakes. You might want to put in a call to the dealership to see if there's any brake related recalls for your vechicle (might be able to find this by checking Jeep's website, too), as it'd be silly to pay a shop for something that you could have done for free.

The proportioning valve could be the problem, there could be a problem with the calipers, and there might be a problem with the brake lines. Having experienced the "joy" of driving a car in heavy traffic and suddenly finding yourself without any brakes, I highly recommend you get this checked out ASAP.

wonky
09-18-2008, 09:42 AM
Yes, brake pads can come loose. I see them now and then in the gutters around town. People pay no heed to the squeaking

There was no squeaking. I'm diligent about squeaking brakes. But the brakes suddenly felt oddly disconnected (though they still functioned pretty normally). I don't think I could describe it any better. The brake pedal just felt... weird.

I double checked with my husband and he doesn't remember any previous brake job, either. And he does tend to remember stuff like that better than I do. So, after 70000 miles, one set of new rear pads and nothing else.

I can take it in to Midas. Is that a "brake shop"? I kinda live in the middle of nowhere, so my options are limited.

It feels like it's stopping well, not squishy or pulling or listing or grabbing or anything odd.

Omegaman
09-18-2008, 12:08 PM
I work at a Dodge/Jeep dealer. If you wan't to PM your vin # I'll check for any TSB's realted to this. It's very uncommon for rear pads to wear out before the fronts, and to be sure, 70,000 miles on any brakes is far above the average, since the outlawing of the use of asbestos. Judging from the diagram of the brakes on your vehicle, I don't see how it would be possible to lose a pad. If it did,it would be a catastrophic failure, the caliper should have locked up, rendering the vehicle immobile.

Best Topics: exploding potato staple stick heavies metal heat pool fast neosporin nose iron filings covers weeble acrylic thermal blanket john sutcliffe espn crushed windpipe death keebler elves jewish battery positive side chuck berry fetish just lunch seattle military clicks was einstein vegan ziploc bags microwave the april witch brahmin accent is teller mute 3 independent clauses wwii german helicopter coke with peanuts investigate someone man hands cheryl ellis jtv iv injury locking guitar case viper v10 weird smiles crumbling shoe soles aztec party homemade mustard gas pheromone cologne reddit what does nip mean red stripes taco bell seat at end of bed called mono e mono meaning dead nigger storage pulp fiction christmas tree not taking water how long to regenerate blood after donation what drinks have potassium 60 billion double dollars will my kitten ever calm down what does livin la vida loca mean drew carey theme songs how to rotate a video in ppt songs with baby in lyrics subaru impreza vs outback dukes of hazzard black characters we are our own worst critics meaning how much meat on a deer restaurant august new orleans dress code left lights on in car why does my handwriting look so bad no one comes to the father except through me meaning dell xps 8900 desktop costco library due date card what does acai berry taste like i like the taste of blood pontiac vibe toyota matrix when do chiggers go away there once was a girl how to defrost hot dog buns special report journey to mars how did biff return to the future hey i resemble that remark