Calipers catching on 92 Subaru Liberty (Legacy) Wagon

[madyson16902]

Hi there

 

I purchased a well looked after 92 Subaru Liberty back in April.  She is in excellent condition all that has needed to be done up to now is general maintenance.

 

After a period of really dry weather it sounds like something is sticking to the brakes.  It is an intermittent problem usually rectified (temporarily) by pumping the brakes, going over a bump in the road and soft braking.

 

It sounds like the calipers could be sticking but not entirely sure.  The brake fluid levels are fine.

 

The brakes have been maintained and the rear brake pads were recently replaced.

 

She hasn't been washed for a little while and have run water around the wheels and brakes.  I am thinking it could be dust or a small rock caught.

 

What do you think?

 

Many thanks.

[heartless]

Jack it up, take the wheel off and take a look. not hard to do.

 

I had a small rock in mine recently that was causing some strange noises.

[Rooster2]

I suspect the guide pins need to be lubed. When not lubed, they tend to not release the brake pad from the rotor when your foot is off the brake. It is an easy do-it-yourself job. Ask us how to do this, if you are wanting to work on the brakes, and not that knowledgeable of how to lube the guide pins. Be glad to advise.

[gbhrps]

madyson16902,

 

Here in Southern Ontario, Canada, we can have high humidity for long periods throughout the year. Maintenance schedules recommend replacing the brake fluid every 4 years, due to brake fluid absorbing water and rusting inner brake lines and parts, and the change it causes to the boiling point of brake fluid.

 

My point being that your caliper pistons may have slightly rusted in the caliper bores and this is causing the sticking. Over the 45 years or so that I've been working on cars, I've run across this condition many times. The piston moves to apply the brakes, but doesn't completely release when the brake pedal is let off, because of the rust ring in the bore (usually at the bottom of the bore) and on the piston won't allow the piston to relax back into the bore.

 

If the problem is not too severe, with a good cleaning and complete reflush of the brake system, the calipers may still be good to use. Remove the caliper from the wheel, and have someone SLOWLY pump the brake pedal until the piston pops from the caliper. Clean the piston and the caliper bore with 0000 steel wool. If any deep pits are found in the piston, then replace the caliper.

 

If it doesn't have any deep pits, flush the bore thoroughly with clean brake fluid, lube the piston with brake fluid and push the piston back into the bore of the caliper. This assumes that the rubber dust seal and the piston seal have been cleaned and have no tears, otherwise they need replacing. Stretch the dust seal over the diameter of the piston, and when the piston is properly aligned with the bore, and its backside pressed up against the inner seal, push the piston completely into the caliper, being sure that the dust cover seal properly seats in its piston slot.

 

At this point, I usually remount the caliper and bleed it, until moving on to the next one , and so on. Once all calipers and wheel cylinders have been bled, I usually go back over all of them again and rebleed them in sequence. This has worked well for me over the years, and only ocassionally have I come across a piston that was too far gone to use again, necessitating a new caliper. Good Luck, should you choose to go this route.

[Rooster2]

Well what ever is wrong, pulling the road wheel and then inspecting the caliper, pads, slide pins lubed, and looking at caliper bores,  you will see what is wrong. It won't be anything exotic, just a "whatever" that needs to be corrected.

[madyson16902]

Thankyou all so much for kindly replying to my post.

 

The noise was that bad that I could stuff around any longer especially as it had something to do with braking system.

 

It went into the repairers first thing this morning as an emergency repair and it was discovered that the front brake pads had completely worn away so it was metal to metal.  So the front brake pads were replaced, brake fluid replaced and the discs machined.  It was done at a cost of AU $270.00.  We were told that we were at the bare minimum legal limit to machining if it happens next time the discs will need to be replaced.

 

So my next question how much does it cost to get discs replaced?

 

I appreciate all of your help.  I want to keep the old girl on the road as long as possible as she is mechanically sound and even though has just over 413,000 kms on the clock is still running like the day she rolled off the show room floor.

[later_Peter]

I just pulled the wheel off my '99 OBW. one of the bolts securing the caliper was loose. Tightened that puppy up & noise went away.

[Rooster2]

Thankyou all so much for kindly replying to my post.

 

The noise was that bad that I could stuff around any longer especially as it had something to do with braking system.

 

It went into the repairers first thing this morning as an emergency repair and it was discovered that the front brake pads had completely worn away so it was metal to metal.  So the front brake pads were replaced, brake fluid replaced and the discs machined.  It was done at a cost of AU $270.00.  We were told that we were at the bare minimum legal limit to machining if it happens next time the discs will need to be replaced.

 

So my next question how much does it cost to get discs replaced?

 

I appreciate all of your help.  I want to keep the old girl on the road as long as possible as she is mechanically sound and even though has just over 413,000 kms on the clock is still running like the day she rolled off the show room floor.

Discs are simply circular chunks of metal, so nothing exotic about them. They just bolt on. In the U.S. cost is about $40, so in AU, product cost would not be much. Doing your own brake work is an easy task to learn, and saves you a good chunk of money, and doesn't take much time. Ask us how, if you want to learn.

[brendanr279]

I'm no mechanic and I just replaced my brake pads and rotors.  The hardest part was getting the rusted on tire off the hub, just took a couple good boots to the tire and it broke the seize.  You can probably find the procedure in detail online or definitely in one of those repair books youcan buy at an autoparts store.  It's real simple though.  Jack the car up, remove tire, unscrew two bolts that hold on caliper making sure to support the caliper so it doesn;t bust the brake fluid lines while its hanging there, use two 8x1.25 bolts to pop the rotor off the hub, place new rotor on (doesn't require bolts, lug nutts hold in place once tire is on), pop out old brake pads from calipers and replace with new (I had to grind down the little nipple on the new ones a bit to get them to slide in easily), bolt the caliper back on, then tire.  Should be good as new. 

 

You may need to use a clamp to push the piston back into the caliper.  Be sure to grease bolts, backs of brake pads, and anywhere there is metal to metal contact (NOT on the surface of brake pad or rotor!!), its recommended you grease the caliper spring-like bolts that allow the pads to recoil after braking or you may eventually get pads rubbing when not braking.  Be sure to buy quality rotors.  I bought cheapos from the part store and they warped after a little more than two years of driving (35K miles).  It's pretty simple.  Once you do one wheel the others will go much faster.

[Rooster2]

I'm no mechanic and I just replaced my brake pads and rotors.  The hardest part was getting the rusted on tire off the hub, just took a couple good boots to the tire and it broke the seize.  You can probably find the procedure in detail online or definitely in one of those repair books youcan buy at an autoparts store.  It's real simple though.  Jack the car up, remove tire, unscrew two bolts that hold on caliper making sure to support the caliper so it doesn;t bust the brake fluid lines while its hanging there, use two 8x1.25 bolts to pop the rotor off the hub, place new rotor on (doesn't require bolts, lug nutts hold in place once tire is on), pop out old brake pads from calipers and replace with new (I had to grind down the little nipple on the new ones a bit to get them to slide in easily), bolt the caliper back on, then tire.  Should be good as new. 

 

You may need to use a clamp to push the piston back into the caliper.  Be sure to grease bolts, backs of brake pads, and anywhere there is metal to metal contact (NOT on the surface of brake pad or rotor!!), its recommended you grease the caliper spring-like bolts that allow the pads to recoil after braking or you may eventually get pads rubbing when not braking.  Be sure to buy quality rotors.  I bought cheapos from the part store and they warped after a little more than two years of driving (35K miles).  It's pretty simple.  Once you do one wheel the others will go much faster.

I smear on anti-seize on the hub, when installing a road wheel to prevent the gauling that you described. Makes it a lot easier in the future to remove the road wheel.