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Hi! I drive a 2001 Honda Accord 4cyl, about 141k miles, with rear drum brakes. The issue I’m experiencing becomes apparent only when going in for my yearly state inspection. During the brake balance test, my right rear brake is apparently “locking up more than the left,” or is otherwise doing most of the rear braking and therefore causing my car to fail inspection due to “imbalance.” The test done is one where the car is driven onto measuring plates, called the “brake plate balance test.” (Correct me if I’m mistaken on the name or otherwise)
I had bled my entire braking system two months ago to replace the old fluid, and at that time checked and cleaned, but didn’t adjust the drum brakes because they appeared to be in good condition despite being the factory original shoes and hardware. The brake pedal felt the same before and after – a little softer than a brand new vehicle but gets the job done well, with no other issues.
Once I received my first failure, I adjusted both rear drum brakes, but the exact same failure result (same imbalance level on the right side) occurred. I then replaced the shoes, springs, and wheel cylinders (since I read faulty wheel cylinders can cause lock-up; and figured my car is old enough), and bleeding and adjusting the rear wheels; only to get the same failure AGAIN… I then adjusted the drums to attempt to correct the imbalance, and retested, readjusted, and retested several times until I finally received a passing inspection with the inspector telling me that something is still wrong with the car and my brake adjustments are only masking the real issue; despite everything I’ve done and replaced.
The car drives and stops just fine – you’d never know anything was up unless you’re getting tested like this…
Has anyone else seen something like this? What are your thoughts? Attached is one of the test results – The right rear brake seems to be where the issue lies, and is denoted by the longest blue bar on the photo.
Thank you for reading this long write up and for the amazing work you do on this site!
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I’m curious to know: Which state is doing a brake balance test as part of their annual state inspection?
You said you replaced the brake springs.
Did you replace ALL of the rear brake springs, or just the ones that hold the shoes to the backing plate?
Some kits just give you the hold down pins and springs but not any of the others.Are all tires the same and are they properly inflated?
You’ve also replaced the shoes and wheel cylinders but not the brake drums?Thanks for your response! This inspection was in Utah, but I’ve never seen one quite like it before around here, and it sounded strange to several friends I talked to.
I purchased a hardware kit with my new shoes and cylinders that contained, for each wheel, the hold down springs & pins, as well as the adjuster spring and return spring. The only original components left were the adjuster lever itself and adjuster screw (which I cleaned and lubed). I also applied hi temp white lithium grease to the parts where the shoes rub on the backing plate.
I forgot to mention that, although I didn’t replace the drums, I took them to my local O’Reilly’s and had them turned. There was plenty of thickness and no obvious round errors.
At the end of last year, I had all 4 tires replaced with the same tire type, and rotated them a couple months ago (figuring it was a convenient time since I had the car on all fours already for the aforementioned brake bleeding).
Although it’s been a little while since I checked, my tire pressure was good. I’ll check them again to be sure though.
Have you had a 4 wheel alignment done on the vehicle?
From what I understand, if a wheel is out of alignment, it can produce drag which will show up as excessive brake force during brake testing. Perhaps your passenger side rear wheel isn’t pointing where it should.
Does the car have independent rear suspension? Brake hoses maybe? Had a brake hose start breaking down & cause a pull when braking. Just a thought.
The last alignment I had done was last fall at my local Honda dealer, I’m not certain whether that was a 4 wheel alignment or just the front. Hmm. Perhaps I’m due for a 4 wheel alignment regardless.
I do believe the rear brake lines are independent, but not sure about the rear suspension. I only see the sway bar connecting the two rear wheels, but I don’t know much about suspension.
You applied high temp lithium grease to the backing plates but did you first scrape off any rust, debris, etc. and are all of the points that the shoes contact free of any grooves.?
This article offers a few additional ideas.
I will add that it is easy to think the shoes are properly adjusted when they actually aren’t.
This happens if the shoes are not perfectly centered/positioned when the adjustments are made and checked.It’s also possible that a parking brake cable is hanging up. This happens most frequently on cars whose owners seldom apply the parking brake.
My backing plate was in surprisingly good condition – with minimal to no rust or grooves; and I sprayed everything off real good with brake cleaner before I installed the new brake components.
I use my parking brake very regularly, and never had an issue with it (always engaged sufficiently between 5-7 clicks); although I’ve never adjusted either the parking brake or drum brakes until now – no apparent issues until now.
Good information in the article, thanks for the link!
Speaking of proper adjustment, do you know any tips or tricks for these Honda drum brakes? I’ve read mixed information on the “proper adjustment procedure,” whether it’s the classic advice of “adjust until the drums drag a little;” per my Haynes manual and other articles; or to do only a “quick adjust” and let the self adjuster take it from there like I understood from the article in the link… I followed the more “classic” advice, this resulted in the best feeling brake pedal for me.
Also, when adjusting my brakes, the rubber plug on the backing plate that you remove to access the adjuster with the drum on is essentially blocked by the rear suspension knuckle – so I’ve been removing the drum, adjusting, putting the drum back on, and testing until the adjustment “feels right.” I found this easier than trying to use that “blocked” access point.
Would this create any issue with keeping the brake shoes centered relative to the drum? Are there any other tips and tricks for ensuring the drum brake components remain centered? Would a special tool like a brake spoon help with hard to reach adjuster access points (I don’t have one of these)?
Also, what’s the best way to adjust the parking brake itself? My system appears to differ from the one pictured in the linked article – there’s no “strut bar anti rattle spring.”
Thanks again for your help everyone!
The “classic” method is what I was trained to do.
Relying upon the self adjuster to actually self adjust enough very often yields unsatisfactory results.
Easiest way to make sure the shoes were centered during the adjustment is, with both drums on, step on the brakes a few times.
Recheck the adjustment after this and readjust, if necessary.
Brake spoons can be helpful but they don’t work for every car.
This style, with a notched shaft on one side, works well for many vehicles
https://www.amazon.com/OEMTOOLS-25239-Brake-Spoon-Imports/dp/B0014WIT3I/ref=sr_1_5?s=automotive&ie=UTF8&qid=1507829566&sr=1-5&keywords=brake+spoon
It has been a while since I’ve done Accord drum brakes so I don’t recall if it will work on your car or not.
Some brake adjusters are best moved with a very thin, small screwdriver.In light of the fact that your RR wheel doesn’t lock up when you brake hard combined with the fact that no one else in your area has been subjected to this supposed part of a state safety inspection–I wouldn’t be so sure that there’s really much of a brake issue going on.
It’s possible to do things to create an undetectable and temporary brake friction difference just for the test.
Don’t really want to post details on a forum, as I abhor aiding the ethically challenged members of society.That’s why I stuck with the “classic method” myself – I felt I got the best results from it. I’m pretty sure I checked my drum rotation again after pumping the brake pedal several times after my final adjustment.
I mean, my brakes will lock up if applied hard and fast enough – it’s a non-ABS system on my car. Hence I never believed there was a problem. Then again, after all the work and writing to this forum the first time I thought I heard the right rear lock up the most during a quick “stomp test” on my street. But I couldn’t tell for sure so it may be hyper vigilance in light of the test. Who knows…
Thanks for the tool link too, but judging from the photo I may not be able to use it for adjusting with the drum on. My good ‘ol flathead screwdriver with the drum off did the job beautifully!
I’m not terribly worried about a problem with my car. Just like before it still drives and stops just fine. It’s a strange test to me and my friends anyhow, as far as state inspections are concerned. I believe the shop just doesn’t want to remove a wheel to check your brakes… But I’ll keep an eye out as always!
Thanks again, Bonnieman, for all your help looking into this, and everyone else for your help as well!
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