rear brakes over adjusting..... (1 Viewer)

[Rodroo]

I sure wish I had the FSM! Thanks for the link. As you can see I am in Kenya, and my internet is pretty doggone slow. Most of the time it is basically dial-up, so i will have to wait till I have a better connection. But that is off topic for now...

You very well may be correct on the what those thrust washers do. But if they don't affect endfloat/axle run out, what does? You understand it to mean that these thrust washers are for adjusting how well the planetery gears mesh? In looking at the diagram I think I can see what you are saying.

Just to be clear, I know just enough about automotive mechanics to get my self into real trouble! So, on this one I am trusting my mechanic's word.

It is almost two am and one of the kiddo's just woke up crying and now I can't sleep. My brain is pretty foggy so I will look at all of this again in the morning.

 

[Spike Strip]

If you have not done it already, I would replace the drum brake hardware, i.e., spring and pin kit, first, before tearing into the differential. As in previous posts, that is what cured mine, along with drums... But the spring kit is cheap (here, at least) and a good place to start.

Good luck... Get some sleep.

 

[Freewheel]

This was a thread that I found when I was dealing with this same problem and I found a possible fix. The soft bendable OEM "C" clips that hold the E-brake lever and the auto - adjust lever to the pin on the leading edge brake shoe are quite thick and hold the levers quite rigidly in place. If you use an old worn out C clip or throw on a very thin "E" clip because you have one around, the adjust lever will have a lot more play than is supposed to and will actually climb up higher on the star wheel and keep adjusting it beyond what it is supposed to do.

It looks like in Spike Strip's pictures earlier in this thread that he has a thin E clip on the pin, (although it kind of looks like an 'E' clip on his "after" picture as well...)

Anyway - New properly size OEM "C" clips did the job for me, and really you couldn't ask for an cheaper fix...
Of course, it's also important to go through all the brake steps in the FSM, adjusting the bell cranks and the e-brake etc.

 

[liveoak]

I had this happen (brakes over adjusting) on my 4runner (86 rear axle) and I fixed my issue with a 1/4 stainless steel flat washer as in the pictures

 

[EscapeWagon62]

I was experiencing the same issue on my back right wheel.
Pulled the drum, pulled the e-brake cable and noticed that the horseshoe clip holding the self adjust pin wasn’t tightened up properly. The loose pin allowed it to ride up higher on the star wheel.
Snugged it up and it works properly now.

 

[ntdb]

Time to revive this thread again...

My brakes are over-adjusting themselves until they overheat.

This adventure started a few weeks ago when I rebuilt my rear brakes with new hardware and shoes. One of my oil seals was blown so I replaced them and the wheel bearings. I did not mess with the bell cranks because they seemed to be working just fine. I also did not replace the auto-adjusting rods though I did clean them pretty well with brake cleaner. I did replace the clips and I believe they're ok although the metal plate that sits on top of the adjuster does have some inboard-outboard play to it. Perhaps that's the root of my problem? There's a groove on the pin for the clip and it seems like the space on the pin where the plate sits is too wide for inboard-outboard play to be highly restricted. I used the hardware kit from @cruiseroutfit but it is worth noting that the spring/cup/pin pieces did not fit into my brakes so perhaps this is another mis-match.

During the first overheating incident I adjusted the brakes out really far and drove home without them. After that I had some success by following this procedure to adjust instead of relying on the auto-adjust from the parking brake. I then adjusted my parking brake until it maxed out at 8ish clicks and thought I had solved the problem. Unfortunately after a couple hundred miles the brakes were again overheating and my parking brake would only move 4ish clicks. Backing out the parking brake helped somewhat but the DS rear brake is still overheating.

I did note while adjusting the brakes that the drag on the wheel is intermittent. What I mean is that when rotating the wheel to test the drag it would follow a pattern of drag-free-drag-free instead of consistently dragging or not dragging. Does this indicate that the drum is not round? This also seems to manifest as occasional vibration at highway speeds, especially when braking. This doesn't completely make sense to me since I didn't have this problem before rebuilding the brakes and I didn't replace the drums...

I'm pretty sure that new drums are my next step but I'm also considering adding washers to the pin that holds the auto-adjuster plate in place. Is there anything else I should consider? Many thanks to anyone who has read this novel!

 

[Seth S]

New drums certainly wont hurt. And if/when you do install new drums make sure that the mounting surface is clean and free of debris. Its easy to have a small piece of rust get in between the drum and hub flange and this can prevent the drum from sitting flat...introducing small but troublesome alignment problems.

 

[Michael Hanson]

Hi, Those that have 4 wheelers know the problems with drum brakes. Dirt and corsion.Also non use,drum brakes do not like not being used. Mike

 

[EscapeWagon62]

View attachment 1677272 I was experiencing the same issue on my back right wheel.
Pulled the drum, pulled the e-brake cable and noticed that the horseshoe clip holding the self adjust pin wasn’t tightened up properly. The loose pin allowed it to ride up higher on the star wheel.
Snugged it up and it works properly now.

I’m going to try two things this weekend since my bragging post that I solved it.....didn’t.
1. I’m going to try the washer trick @liveoak used.
2. And this is what I THINK the issue might be, the pin that comes through the backside of the brake assembly (where I bragged about my horseshoe clamp and @liveoak mounted an extra washer) isn’t seated all the way. That would move it closer to the adjuster wheel and theoretically allow the adjuster to to move too high on the wheel and thereby over tightening.

 

[Michael Hanson]

Drum brakes need regular adjustments and cleaning .They are no way as maintain everything

 

[Michael Hanson]

Sorry hit the wrong button, they are no way as maintaince free as discs.

 

[liveoak]

I have not had the issue come back on mine since adding the washers, hopefully they are still self adjusting. I think the trick is to get all of the slack out of the pin so that the adjusting arm isn't able to wobble around at it's pivot point. Depending on the play, it could take a thicker or thinner washer to get the desired result.

 

[ntdb]

I took my drums to be turned and the shop said they were super warped. I’m hopeful that this helps!

 

[ntdb]

Nope. The brakes have over-tightened themselves again after just a hundred miles. This is so frustrating.

 

[EscapeWagon62]

It seems to be fixed finally.
After my brakes over tightened again I’ve made four adjustments/replacements
Note I previously installed new OEM drums which had no affect.

Here is what I did:

1. Replaced rear shoes with a brand new OEM set. These came with the pin that the e-brake and self adjuster mount on pre-installed vs the aftermarket ones I had on there (I had to pound the pin into the aftermarket shoes). The aftermarket pin was loose but the horseshoe clip likely held it in the correct place so I don’t think that was the issue.
2. I remembered to lube the back plate just in case the shoes were binding On the backing plate.
3. I installed a wider washer as @liveoak recommended. The previous washer I tried was on the smaller outside diameter size
4. I replaced the tension springs with OEM in case the aftermarket ones were weak.

My belief is that the washer recommended by @liveoak is the cure, the washer just has to have a wide enough outer diameter to affect the lateral movement of the self adjuster lever. A washer fits quite nicely behind the auto adjust lever with room still left to install the e-clip towards the end of the pin.

Why this tends to happen to rear right vs left wheels is probably a mystery that will never be solved.

TOP TIP - when reinstalling tension springs, use a ratchet strap around the brake shoes to pull everything close. It really helps when you stretch the springs onto the shoes.

 

[cps432]

It seems to be fixed finally.
After my brakes over tightened again I’ve made four adjustments/replacements
Note I previously installed new OEM drums which had no affect.

Here is what I did:

1. Replaced rear shoes with a brand new OEM set. These came with the pin that the e-brake and self adjuster mount on pre-installed vs the aftermarket ones I had on there (I had to pound the pin into the aftermarket shoes). The aftermarket pin was loose but the horseshoe clip likely held it in the correct place so I don’t think that was the issue.
2. I remembered to lube the back plate just in case the shoes were binding On the backing plate.
3. I installed a wider washer as @liveoak recommended. The previous washer I tried was on the smaller outside diameter size
4. I replaced the tension springs with OEM in case the aftermarket ones were weak.

My belief is that the washer recommended by @liveoak is the cure, the washer just has to have a wide enough outer diameter to affect the lateral movement of the self adjuster lever. A washer fits quite nicely behind the auto adjust lever with room still left to install the e-clip towards the end of the pin.

Why this tends to happen to rear right vs left wheels is probably a mystery that will never be solved.

TOP TIP - when reinstalling tension springs, use a ratchet strap around the brake shoes to pull everything close. It really helps when you stretch the springs onto the shoes.

View attachment 2430276

View attachment 2430277

View attachment 2430278

Wow, that’s a great idea with the ratchet strap! Top tip indeed!

 

[ntdb]

It seems to be fixed finally.
After my brakes over tightened again I’ve made four adjustments/replacements
Note I previously installed new OEM drums which had no affect.

Here is what I did:

1. Replaced rear shoes with a brand new OEM set. These came with the pin that the e-brake and self adjuster mount on pre-installed vs the aftermarket ones I had on there (I had to pound the pin into the aftermarket shoes). The aftermarket pin was loose but the horseshoe clip likely held it in the correct place so I don’t think that was the issue.
2. I remembered to lube the back plate just in case the shoes were binding On the backing plate.
3. I installed a wider washer as @liveoak recommended. The previous washer I tried was on the smaller outside diameter size
4. I replaced the tension springs with OEM in case the aftermarket ones were weak.

My belief is that the washer recommended by @liveoak is the cure, the washer just has to have a wide enough outer diameter to affect the lateral movement of the self adjuster lever. A washer fits quite nicely behind the auto adjust lever with room still left to install the e-clip towards the end of the pin.

Why this tends to happen to rear right vs left wheels is probably a mystery that will never be solved.

TOP TIP - when reinstalling tension springs, use a ratchet strap around the brake shoes to pull everything close. It really helps when you stretch the springs onto the shoes.

View attachment 2430276

View attachment 2430277

View attachment 2430278

Are your brakes still behaving? Did you add the washer behind the two plates pictured in the last photo? I'm about to add a washer to mine and it seems like the "right" spot would be immediately behind the C/E clip but I've seen you and @liveoak put them further back.

 

[EscapeWagon62]

It did fix my issue and Ive been testing it out for a couple months without reocurrance.
The correct placement is behind the circlip AND behind the brake adjuster lever.
My hypothesis is that my adjustment lever hole had been expanded over the years and allowed the lever to rotste/angle up higher on the adjustment star wheel. Its also my hypothesis that the lever would stay up high on the starwheel putting constant over adjust pressure on the brakes and over heating them.

Either way....place it directly behind the adjustment lever snd you should be good to go, It may work, as you noted to install it behind the circlip but I couldnt know for sure.

 

[Chad717]

So glad this thread got revived. I have been driving my 60 after finally getting it through Colorado emissions. I rebuilt both rear drums a little while back and after that I noticed the rears were getting pretty hot after a drive. ( I wasn't driving it much, mainly testing out emissions stuff) I took it to a shop last winter to look over anything I had missed on the emissions junk. I talked to them about the rear brakes and the one guy there who knew Cruisers said he would adjust them. He did, and I brought it home and didn't think much about it.

Now that I am able to drive it I started to get a vibration around highway speeds that was never there before and it would get worse under braking. Then it would go away and come back. I'm assuming one of the brakes is sticking and then loosening up some, but I'm really not sure. I brought it home a couple days ago after a drive where this was happening and I shot my temp gun at the brakes. Both front disks were 170 ish and the right rear was 160 ish. The left rear however was over 300. So I pulled off the drum and everything looks normal, but there is a lot of brake dust and the front shoe is worn more than the back shoe. I am ordering toyota parts today and I am going to attempt to rebuild it. Here is a video of my adjuster moving. Not sure if anyone can tell much, from it.

 

[EscapeWagon62]

Watching your video it appears that the pin that your brake adjuster sits on is incredibly loose.
Do you have the horseshoe clip attached?