- This topic has 7 replies, 6 voices, and was last updated 11 years, 3 months ago by
.
-
Topic
-
Vehicle: 2006 Toyota Corolla CE 1.8L Rear drum brake front Disc.(front disc brakes all new pads/rotors)
116K milesA few months ago I changed the rear brake shoes on the car. Everything was fine a functioned as normal.
The other day I noticed some noise coming from the rear brakes so I decided to take a look at them. Before I torn it down I took the car for a test drive and did a few hard stops and noticed that the right rear wheel would lock up if I gave it to much pressure on the pedal. This concerned me So I went in and re cleaned the drums and re adjusted them. I also check the assembly for anything out of the ordinary (didn’t find anything) Then I took some light sand paper and cleaned the face of the shoes off in case there was some contaminates on the shoes. All of this didn’t not fix the lock up issue.Any idea as to what can cause this? Bad proportioning valve? Any way I can test for that?
Could an out of round drum somehow cause the wheel to lock up on hard stops?
Can I put new drums on the old shoes? (they are only 2 or 3 months old and have full pad life on them)
Maybe the shoes are bad somehow? I Don’t see any contamination? Also this is only happening on HARD stops. Any other time they function normally.
Thanks in advance.
-
Replies
-
While this may be a bad proportioning valve I would check a couple things first. These don’t go bad that often.
Assuming it is correctly put together and the parking brake is retracted and not applying tension….
Check the brake line that goes to the right rear for any bends, kinks or damage. If this is fine, then I would suspect your brake cylinder. How does it look. Also, you can remove the drum and have someone hit the brakes and see how it is working. I would remove the cylinder and carefully have someone apply the brakes and catch any fluid that should come out. if fluid does not come out or barely, you have an issue elsewhere. If fluid comes out with no issue I would re install the cylinder and re bleed the system. The good news is that these cylinders are not that expensive.
Karl
Wheel cylinders look fine. No fluid behind the dust boot. I don’t understand why a leaking wheel cylinder would cause the wheel to lock up only on hard braking. I would think that a wheel cylinder to which is defective would cause low brake pedal/low fluid level in addition to a contaminated shoe lining. I have none of these symptoms. Also I was told that applying the brakes with the drums off the vehicle can actually damage the wheel cylinder since it has nothing to stop up against.
Thoughts?[quote=”autotech09″ post=68846]Wheel cylinders look fine. No fluid behind the dust boot. I don’t understand why a leaking wheel cylinder would cause the wheel to lock up only on hard braking. I would think that a wheel cylinder to which is defective would cause low brake pedal/low fluid level in addition to a contaminated shoe lining. I have none of these symptoms. Also I was told that applying the brakes with the drums off the vehicle can actually damage the wheel cylinder since it has nothing to stop up against.
Thoughts?[/quote]It may be a sticky cylinder. The trick with applying the brake is to go slow, release the brake and push the shoe assembly back in place.
Measure the drums. Check to see the are not out of round.
Bleeding the rr wheel may reveal issues.
Also did you equally set the adjusting wheel on both sides when you replaced these brakes..
actually the wheel that is locking up may not have
the problem.The wheel that does not lock up may have
the problem.I would replace the wheel cylinder on the
wheel that does not lock up. Both wheels should lock up
under hard braking.If the symptom gets better with the wheel
cylinder replacement.Due the other side also.I once read in a textbook of a scenario where a technician did rear brakes and the brakes were locking up based the fact that the hardware was almost the same except for one spring. Make sure you use the exact hardware for the vehicle that you are working on. Also compare the specs of your drums to the specs of the manufacturer. Finally, you should strip down the brakes in question and check each component one by one if there is anything unusual replace it as you go along.
- You must be logged in to reply to this topic.