Noticed that the LR wheel had a lot of brake dust on it.


So I promptly started inspecting the rear brakes. I found that both the inner and outer pads on the left side were half the thickness of the right side. But the slider pins were free, and both pistons retracted into the calipers OK. Inner and outer pads wore the same. The pads were not stuck in the stainless guides, either.

Can't feel anything funky in brake operation: no noises, no pulling to one side. Both sides of the wheels are cool after driving.

The TL has 175K miles on it if that matters. Rear brake parts are original (except for pads).


Anybody want to hazard a guess as to the cause of this problem? I've buttoned everything up for now...

 

the side with low pads is the side working!
the other side of the car is not~

for some reason our rr caliper does like to fail
Do you keep up on brake fluid changes every few years?

 

Check the other side now and see if you have the same results of every thing moving freely.

 

I did check both sides with the comparison as noted. Brake fluid has been changed religiously every three - four years, but it's due again.

Oh Yeah, I DO know that when one side starts working extra-hard it's sometimes the other side with problems (if its a caliper)

I did check both.

After the "brake service" I think the problem is OK for now (except that I'll be ordering new rear pads sooner than later). Have driven the car about 1000 miles since Sunday.

Any history on TLs to believe that one caliper piston could be hanging up just in one spot (and maybe I free'd it when I retracted the pistons to check)?

My other thought is a partially restricted rubber brake hose...

Thoughts?

 

If its not the slider pins then its probably the piston in the caliper. One side is working better than the other. The rubber hose shouldnt be partially restricted. Nothing could cause that. One way to know is if it bleeds properly.

 

Haven't tried bleeding yet.


When rubber brake hoses age and swell internally, you can apply the brakes and they won't allow the caliper to release. After a while, they slooowly allow pressure to drop.


My brake inspection had been done after the car had been sitting three-four hours. But like I said, I checked the wheel hub temp with my hand every few miles for 30 minutes of driving after my inspection, and both sides were equally cool to the touch.

If 01tl4tl says the RR caliper piston is suspect, I'll replace both calipers the next time I change pads. I haven't read about any TL brake hose failures, but I wasn't sure. (On many Chrysler Corp vehicles, brake hoses have collapsed that were only five years old...)

Thank's for the input, guys.

 

I would inspect the caliper operation, then get a rebuild kit if possible
your 3 year program of fluid change is at the limit,,1 year is really good plan
old fluid collects moisture and can pit the piston-cylinder wall of the caliper
If the surface is good = 20$ rebuild kit has new orings,,simple diy

I mention this because rear calipers cost more than the fronts- due to park brake lever
75 per a few years ago when I did mine

 

Here's the best way I've found to test for restricted hoses. With the wheels off the ground, start the car and apply the brakes HARD. Hop out and see if any wheel is bound up. If so, crack open the bleeder. If the wheel is now free, it's likely the hose. The proper diagnostic approach is to start at the master cylinder and open each fitting till the wheel spins free, but 9 times out of 10 it's a hose. We had a 1 of 10 last week on an old dodge p/up... master cylinder was holding pressure.

 

With all due respect Kris, hose restrictions are fairly common. They seemed to be extremely rare in the 70's and prior, but we see at least one a month even in our small shop. I can't really say which car lines have higher failure rates. I'll start paying more attention.

 

FWIW, Centrix or Raybestos reman rear calipers are $65 - $70 per side @ Rock Auto.
I realize that these are probably just the caliper side of the assembly, but that's worked well for me in the past.

I'll def. try the diagnostic from TLer Trash before ordering the parts. Thanks.


The parking brake on Gen2 TLs are the drum-in-hub type so I can't see that being a factor in cost, though.

 

go look at your rear calipers and see how the cable for the park brake is attached thru a mechanism

how many ACURA TL brake lines do you see fail in a shop is the question
old dodge chevy fords dont count in this discussion
True- there have been a few reports here, but those were extreme weather conditions iirc, rusted out the metal lines too!! maybe a Canada or Alaska car?

Probably not keeping up with brake fluid changes is a major factor

the easy way to tell if the TL has a line problem is break the bleeder loose and close it- have helper push pedal as if stopped on a steep hill
Open bleeder- crud and or fluid comes shooting out--or it doesnt

NOTE for safety of the master cyl- place a 2x4 wood block under brake pedal arm-
limiting it to its normal amount of travel--3/4 of the way to the floor
do NOT push the brake pedal to the floor with bleeder open!!!!!

 

I'll check but with the drum-in-hub parking brake, would that affect the disc service brakes?
That's the method I always use, well maybe not a 2X4, but a 1X3 works good! Important thing is not to bottom the piston in the master.

When I return from my trip I'll dive in....it's been OK in 1000 (highway) miles.

 

The problem with checking for hoses this way is that it doesn't work very well. You have over 1000 psi when you apply the brakes hard, and the flexing of a square cut ring in the caliper to push the piston back. That's how the caliper can apply, but not release with a restricted line.
In case you were sped reading, the old dodge did NOT have a restricted hose. I can't give you a % breakdown, but acura and honda aren't especially good or bad with respect to other cars as far as hoses go, but they do fail.
I can't figure out what you're trying to say about the parking brake cable or bracket; they don't attach to the caliper or influence it's operation in any way.

 

Im not saying its not possible. If the calipers were taken off to replace pads and the line was twisted it could cause it or if the rubber line were degrading it might but for the most part its highly highly unlikely that there is something in the hose. Its more likely that a caliper is hanging up or not working as well as the other or a bad set of pads.

Rear caliper issues are becoming very common now on these cars as they age. The sliders and pistons need to be replaced/rebuilt fairly commonly with age now.

 

No need to look for a problem there, the parking brake its a drum and has nothing to do with the rear brake pads or excessive brake pad wear so there is nothing to look for there.

 

I'll agree that calipers are far more commonly the problem, especially the ones that have built in parking brakes, but we've been stung often enough by restricted hoses, that we routinely check for them. I've never made a connection to the abuse that a recent brake job might cause [twisting, clamping off, letting a caliper hang, etc], but we usually look a little closer if there appears to be recent work. Most often if it's a problem with recent repair, it's to correct a problem that wasn't caught the first time. Like a new caliper on the corner that now needs a brake hose.

 

Just as a follow up, the LR brake started to seize. (got HOT!)

So I replaced both rear calipers with Semi-Loaded rebuilt units from Advance Auto. (Complete caliper assemblies, no pads) Got a nice pair of rear ceramic pads there too. Flushed the brake fluid at all corners..


Oh Yeah, replaced the hood supports ("gas shocks") too (they were getting weak). Oil change, other maintenance...good to go!

 

 

there goes my- `the RR is often the culprit` theory,,but I was correct about caliper failure!!
wheres my bonus diagnoser points for this one?

 

You got 5000 points for guessing the caliper, but because you guessed the wrong side, you lose 3000. That only nets you 3rd place.

:bronzecup



I've seen bad calipers lots of times, but it faked me out this time since it retracted readily when I first checked. Guess it had a rusty spot that caused the sticking after another 2000 miles. Like you said the bad caliper could have been the other side.

Most drivers would not have noticed the excess brake dust so I want props for correcting it before the rotor was ruined by metal-on-metal.



Anyway, it's a happy ending.

 

someones daughter recently said- my front left brake makes a noise
Quick visual revealed a scale relief map of the Grand Canyon on the rotor!!
well past full metal backing plate to rotor contact,,,that started a few months ago~