01 Outback 2.5l brake caliper seized, now wheel grind

[Rustyboot]

I've got a 2001 Outback 2.5L with 186,000 miles.  About a year ago I replaced the front passenger side brake caliper after it froze up.  A couple weeks ago the same caliper froze up while I was on the freeway.  I drove a few miles to an exit with the steering wheel vibrating hard and towed it home.  After replacing the caliper again I get a heavy grinding that is consistent with the rotation of the wheel.  It sound like grinding brakes but real loud.

 

Here are the steps I have taken before getting stuck:

-checked brake lines, all look good

-checked brake fluid, bled out all air, it looks clean and fine

-installed new caliper

-new brake pads on front brakes (old pads on passenger side had worn at a slight angle not parallel to back of pad)

-had the rotor turned at local auto parts store

 

I'm definately no mechanic but try DIY as much as possible.  I was thinking it could be a bearing or bad axle but not sure.  Any help on troubleshooting and how to fix would really be appreciated. I cant really afford to pay a mechanic

 

 

[Rooster2]

When you install new pads, are you putting anti-seize on the brake pad sliding surfaces, and also on the slide pins? It is very important to add the anti-seize to the slide pins, otherwise the pins can bind without lubricant, and not release the pad properly from the rotor, when you take your foot off the brake pedal. When this happens your pads drag, particular on the side with the stuck pin, and will wear down the pad at an angle, and eventually with the pad worn down, will grind brake pad metal to the rotor metal surface. It is pretty easy to tell if the grinding is on the rotor, as there will be circular grooves worn into an otherwise smooth rotor surface.

 

If it were me, I would pull the road wheel, and the caliper looking for abnormal pad wear. It is unlikely that your relatively new caliper is the source of this problem. However, if so, you may have a life time from the parts store, and get a replacement caliper at no cost.

 

Keep us posted on what you find, and how you are repairing this problem.

 

Hope this advise helps!

[Rustyboot]

-Rooster2

Before I had the rotor turned I did not notice any grooves in it.  I did grease the sliding surfaces of the new pads and the pins on my new caliper came pre-greased.  I have only driven the car around the block since replacing the caliper, pads, and turned rotors.  If it was a stuck pin wouldn't it be a constant grinding rather than a pulsing grinding that mimics the rotation of the tire?

[johnceggleston]

it is probably the backing plate.

check the backing plate to make sure it is not rubbing on the rotor.

this is common. turn the wheel by hand with it in the air until you hear the scraping.

 

take it apart again and remove the rotor.

it may be mounted cockeyed, or crooked.

it's rare but it has happened.

does the wheel turn true or does it have a wobble?

 

did you get the bolts on the caliper seated correctly?

they bolt in to the slide pins, ?

Edited April 24, 2013 by johnceggleston

[idosubaru]

*** Was this grinding present before the caliper replacement or only after replacement?

Is the dust shield rusty, bent, falling apart?

 

stuck caliper can pulse when they first start....i've heard it before particular if it's the beginnings of being seized due to the swollen pin bushings i'll mention in a moment.  it'll get snug, too tight, but not completely seized and the rubber swollen bushings allow some give/play. they will also wear unevenly and the geometry of the pads is affected because it'll be one pin, not both usually.

 

wheel bearings may be shot but weird for that to happen right when the caliper seized.

(the failing caliper may have previously degraded the already low and aged grease and pushed the bearings to their grave, but that would be uncanny timing)

 

if you have an infrared temp gun - hit the front wheels with it after the next drive.  a failing bearing will generate lots of heat.  take multiple measurements on both sides as the variations are wild sometimes before you can see a trend.  won't take long to show a huge difference though (high's and lows).

 

Subaru calipers generally don't need replacing, even here in the rust belt where bolts shear off, we have to drill stuff out regularly, the bleeder screws shear off all the time, caliper slide pins are routinely removed with torches, and brake lines rust through - we have much harsher conditions than you have and even in these conditions i've never seen a Subaru caliper that needed replaced, two that leaked but were rebuildable....it's really rare, so I'd keep my eye out for another cause.

 

a collapsing brake hose will cause the caliper to seize. but, i'm doubtful as i've never seen it happen in a Subaru. they fail internally and when you press the brakes, they work as normal. but when you let off the brake pedal the hose is collapsed internally and won't allow fluid to back out of the caliper (or does so slowly since there's less hydraulic pressure to return than to brake) or the caliper to back off the rotor....so it acts like a seized caliper.  in those cases the brake hose needs replaced and there's no way to really test the hose.  i jack the vehicle up and by pressing the brake and letting off you can feel the wheel stop when the pedal is pushed...then still be hard to turn when the pedal is left off.  let it sit awhile and it'll spin freely as the pressure slowly bleeds off...repeat to verify collapsed hose.

 

also - throw the pin bushings away, they are a nightmare.  i've seen a bunch of them seize.  sometimes right after a brake job...pure speculation that being exposed to new grease or something causes them to swell in the bore and they seize frequently after a brake job.  whatever the cause - i see this happen all the time. starts off as light squeaking noises as the rubber bushing is swollen in the bore...then progresses to unevenly warn rotors and loud noises and it gets seized as over time the rubber bushing is smashed into the bore.  maybe it's more prevalent here in the rust belt because boots/grease get compromised easier because i don't see many people talking about them but they are a total PITA. it's so common i've been throwing them away for years and I'm all the better for it.  older subaru's never had them, there's no symptoms without, so they're not worth my time.

Edited April 25, 2013 by grossgary

[Rustyboot]

Ok so the issues continues. I removed the wheel, caliper, and rotor yesterday to identify what was grinding. The backing plate was not touching, all pins are new and greased, and everything was mounted square. I found 2 grooves on the top side of the caliper where the rotor apparently is grinding on it. My thought was maybe the rotor was not truly round and had a hump in it so I bought and installed a new rotor.

 

Took it for a test drive and the grind persists. The grind is quietest when driving straight, louder when making right turns, and loudest when turning left.

 

Thanks for the help. I'm determined to get this fixed

[idosubaru]

excellent, nice leg work.  as i suspected i didn't think this would turn out to be a seized or failing caliper.

 

is it possible you have a different caliper than the original, slightly different size?  Subaru was quite freaky about brake changes, they made them all the time and there are a few different dual piston caliper pad varieties from 99-02 that get confusing....wonder if one caliper could be slightly different than another...or rotor for that matter?

Edited April 25, 2013 by grossgary

[Rustyboot]

grossgary

 

I don't think I got the wrong caliper, rotor, or pads.  I got the caliper and pads from Napa based on the specs for '01 Outback 2.5L in their system. And the same for the new rotor from O'Reilly Auto Parts. I'm also skeptical that the rotor or caliper is the wrong size because they only grind once (or in one spot) per rotation of the wheel.  Also why would the grind be loudest during left turns, then right turns, and quietest while going straight? I'm definately not a mechanic, a plumber actually, but I keep thinking it is the wheel bearing.  My thought is, that the bearing had been going bad for a while and eventualy crapped out on me, which caused the old rotor to grind overheating and seizing the old caliper.  I never noticed the grind prior to the old one seizing but I typically drive with music on, windows down, and not slow enough to hear the grind with each rotation.  What do you think?

[1 Lucky Texan]

 

 

If the bearing is that bad, you should have a coupla mm or more movement when rocking the wheel up-down/12 o'clock-6o'clock.

 

I think around 02, some folks have found 2 different sizes depending on manufacturing date.

 

If you have the old rotor, or if the opposite side is not grinding - well, I guess I;m saying, take he old or good parts with you and compare 00 years to 03 years. measure the rotors's diameters.

 

I know there was a mid year change in rotor size, plus, as mentioned, the possibility someone has swapped in the wrong parts.

[johnceggleston]

yes, compare the parts you removed to the new parts.

this couls well be the problem.

 

if not it has to be the wheel bearing.

 

did you loosen the axle nut at any time?

how many miles on the wheel bearing?

 

does it grind when you turn it by hand without the wheel?

[idosubaru]

yep, wheel bearings.

 

i'm surprised it got this bad, having noticeable play and you never noticing or commenting on prior issues before.  but i guess the loud music was a key player we didn't know. LOL

 

a temp gun will verify it if you're still doubtful.  but i'm not.

 

this isn't your issue but ordering the right year/make/model for a Subaru doesn't guarantee getting the right caliper/rotor/pad.  there's a comprehensive list detailing the vast array of brake combinations and it's mind numbing and convoluted, leading to confusion.  i bought 2002 OBW brake pads for my friends OBW and they were not the right pads...hers were different and i had to order some odd ball year Subaru to get the right ones, match them up visually.   I own two of the same vehicle and a close friend has one as well - all 2002 and 2003 with the same brakes....hers were different for some reason.  I have a thread on here about it.  But here's the thing - that story is not rare or anecdotal, happens fairly often with Subaru brakes.

[Rustyboot]

Thanks for all the responses. My Chilton book book recommends having a mechanic replace wheel bearings? What are your thoughts? I live in Seattle, Les Schwab quoted me $285 not sure if anybody out there has a Seattle Subaru mechanic they recommend.

[idosubaru]

couple of options:

1.  get a used knuckle assembly and just swap it out yourself.  fairly easy job and can be done for $100 or less.  $50 for knuckle and $25 for a new ball joint. it's not a bad fit considering how easy the job is, particularly in an area like where you live with no rust.  ball joints and tie rods pop right out compared to out here.

2.  remove the knuckle and take it with bearings and seals to a machine shop or garage willing to do it and have them install the bearings.  $35 - $70 labor plus bearing parts

3.  install the bearings yourself.  you need a hub tamer or other tool like this, which I use and folks have posted instructions for using:

http://www.harborfreight.com/fwd-front-wheel-bearing-adapters-66829.html

 

It's not terribly difficult but it does take some serious effort to get the bearings out and to wrench them back in, even with that tool.  Gotta keep the threads of the tool oiled or they'll strip with all that force.  Air tools are nice for simplicity but it's easily done by hand too.

[Rustyboot]

thanks grossgary. I'll keep you posted

[CNY_Dave]

Just be aware the usual strategy of 'right turn it gets quiet means right bearing is bad' (and vice versa for left/left) sometimes isn't true... I had a front on my '03 that tried to trick me. Bad left bearing got quieter when it was loaded up in a right turn.

[Rustyboot]

Replaced wheel bearing and ball joint. Took it for a test drive, the grind is gone and we're good to go