I've always had issues with the rear brakes pulsating on my 2004 Tundra and have replaced EVERY single brake component, including the drums. The pulsating actually got a little worse after replacing the drums, so I believe the primary cause is warped drums. Rather than spend another couple hundred on new drums (existing ones are less than a year old), is it possible to have them turned like you do a rotor?
I've also always had issue getting the parking brake adjusted properly. The star wheel just will not rotate like it's supposed to when everything is connected. If I remove the spring that pulses the shoes together and tug on the transfer cable, the wheel advances just fine, but once everything is installed it is very difficult to advance. And I believe they are supposed to auto adjust by backing up the vehicle and applying the brake, but this also does nothing. I have adjusted the cable and everything is within spec. The only thing I haven't replaced is the main brake cable itself, but I don't think that is the issue given the star wheel adjuster does not operate properly with everything connected up. And the only way I can get the parking brake to hold is if I adjust the shoes farther than I feel I should have to, which could actually be overheating the drums and causing them to warp shortly after replacing them actually. Not sure what else to do.
Yes. But, its getting harder to find shops to do it. Some still will.
The problem is, the "trade rules" have changed on this a bit due to the world we live in and sue happy people. The thickness's have been increased. In other words, if they are worn very much, the tolerance is most likely near its limit. No one wants to take responsibility for cutting a drum too thin now days.
Another issue is, the cost of turning is not too far off from buying new ones. Don't mistake that statement, as it is still cheaper to turn one.... if they will.
Pulsating is most often related back to the brake booster. The big donut looking thing which the master cylinder is attached to, usually mounted on the firewall under the hood.
Depending on many factors, year, brand, model etc.. I'd look into that.
Also, air in the line or system somewhere may cause pulsing.
I don't think it's the brake booster because it pulsates if I apply only the parking brake. I did this to rule out the booster or a hydraulic issue. I think the issue is related to the adjusting mechanism, which causes me to over adjust the shoe clearance just to get the parking brake to hold, and the shoes are dragging more than they should when the brake is released , thus causing excessive heat and warping drums shortly after replacement. I really wish I could figure out why these adjusters are so damn stiff. I replaced them just to rule them out and no difference. Other than the main cable, the only other thing I haven't replaced is the backing plates. I suppose they could be warped and putting uneven pressure on the shoes this binding up the adjusters?
Very well. AFAIK, the emergency brake only applies to the rear brakes (as you know), and the emergency brake only works mechanically. Its all mechanical moving parts. No fluid, no software etc (as you well know again).
This is a stumper here......
By chance could it possibly be a transmission issue in some respect?
That could be a software issue. Just throwing out generic ideas outside the box.
I'm certainly not saying is not a drum, but I dont think I have ever run across that.... especially since you have already put new ones on it. That would really be wild...lol
Maybe I'll try replacing the backing plates and see if that helps. They're cheap enough. Maybe I'll post a video sometime soon so you guys can see what I'm referring to with the adjusters binding up.
The attached video is of a 2000 Tundra, but is the same design. My adjusters do not click when I pull on this cable. It's as if the adjusters are jammed. Additionally, to get my parking brake to hold, I have to tighten the main cable so much that the mechanisms at the rear of the backing plate (shown in the video) are not resting on the plates like they're supposed to. I'm pretty sure the issue is the adjusters binding. I just don't know why they are binding. Again, I have replaced every component including every little clip, spring, washer, adjuster, etc etc.
I also attached a screenshot from another video that shows the adjuster mechanism. I don't believe the wings (or what have you) on my adjusters extend back as far as what is shown. In fact, probably only half that distance. I've always wondered why the ends of the adjuster never fit all the way in the slots in the shoes. That could very well be my issue. The adjuster is just under too much pressure because it isn't seating properly. Guess I could try grinding out the opening in the shoes a bit to open them up and hopefully allow the adjusters to fit properly. Very odd.
do they click when turning the star wheel out on the adjuster?
should be able to turn drums on the same machine they turn rotors on but there a little different but still have max diameter specifications where they cannot turn them due to the drum being to thin to safely turn.
I've always had issues with the rear brakes pulsating
it pulsates if I apply only the parking brake
A little confusion here. How can there be pulsation with the parking brake, it's never applied when the vehicle is moving?
Drums can be a PITA, if this is pulsation when applying the brakes, yes an out of round drum could be the issue, just because it's new drum doesn't mean it was machined correctly.
You should be able to turn the drums and slowly turn the star wheel which spreads the shoes, as the shoes get closer to the drums they should start touching consistently. If something is out of round then you will start hearing an intermittent noise.
It's also possible that the shoes could be a problem.
I did a test to isolate the issue to the rear brakes...I applied only the parking brake while driving and the rear brakes are definitely the cause of the pulsating.
Although I can manually rotate the adjusters, it takes more force than it should, and the fact that they dont adjust automatically when when tugging on the cable makes me believe something is wrong.
I used all OEM parts., and have been struggling with this for years. I've replace the drums at least two times. I'm pretty confident the newest drums are warped, but I can't say for sure they were warped when I bought them or they became warped shortly after (potentially due to the inoperable adjusters).
I don't know that I've ever heard of drums warping. They typically get turned to remove scarring from worn shoes. I haven't had any drums [or rotors] turned in yrs. Easier to buy new ones than find a place that still turns them and whether or not the drum/rotor would still be in spec once turned. You should be able to manually turn the drums and judge if they are out of round.
Pulled a drum today to check the adjuster, and it looks to be fully seated. Although it does not advance when I tug on the cable. FYI, I put the bar clamp on after trying without initially, to see if it would make a difference, but it didn't. Sorry for the shaky video.
Oh, I used Brembo drums from Rock Auto. Guess I'll replace them with OEM.
Replaced the drums with OEM and the pulsating is gone. The OEM drums are actually balanced too, and have an anti-corrosion protectant on them. Should have just installed these to begin with. Hopefully they stay true.
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We have had a swarm of catalytic converter thefts in my area. I have a 2012 Dodge Ram that sits outside a lot that I would like to help protect. The local parts stores are all telling me that the thieves are getting around the cables and shields with rotary die grinders instead of reciprocating saws. Is there something better out there?
03-23-23, 06:26 PM
