2016 Crawl Mode & Drum Brake Explanation, & Misc. Info & Hyjacked Back To Drum Brakes, BS & ???

This guy reviews it..
https://www.youtube.com/embed/0-x_vRnfeKE

 

Guys. The reason your drums were fine for so many miles is because they were improperly adjusted for long stretches. That's like issue #1 with drums. They don't stay at the ready with each pedal press like disc.

What you're giving as great kudos to drum is its worst point

 

This isn't a drum brake defense thread, I'm just reposting vids that give some explanation to some of the various lingering questions out there...

 

That may be true--I'm no expert on brakes. It might be useful if someone knowledgeable (and I don't mean just opinionated) could give a rundown of the advantages of each braking technology. I've read a lot of outraged opinion on the drum brakes on this site, but have gained very little knowledge from the reading.

 

Drum brakes have been argued to be better for towing because as you push into the pedal and the shoe moves out to contact the drum, the force of the rotating drum pulls the shoe & mechanism into it supposedly creating better stopping performance.

Downsides are that its not self-adjusting. So over time, the shoe wears and it gets too far away from the drum surface to contact enough to be effective. There's also the issue of trapping contaminants in the drum itself. If you go through water or mud of sand or whatever it will get in there and destroy your stopping abilities. Quickly. Also it means if your rear outer axle seal goes in any degree, the oil will be funneled into your brakes and also kill them good.

Discs don't suffer these disadvantages.

 

For most people doin regular driving they are fine (drums). Get them properly set at good intervals and you won't care. For my old rig i converted to disc for better and more reliable stopping performance through all the gunk I'd find myself in.

Upshot to drums is less brake dust

 

That is interesting. Mr. Sweers (sp?) seemed to say that an advantage of disc brakes is that they were BETTER for towing in that they were more fully ventilated (not a quote from him, but the gist as I understood it). He also seemed to give as his reason for retaining drum brakes on the Tacoma is that they were LESS likely to trap road debris, though you and he may mean different grades of debris--he meaning larger debris and you meaning particulate debris.

I wasn't up on the problem with adjustment. That's a real disadvantage and it makes me wonder whether it is a good idea to mix brake types on the same vehicle. If the brakes are all drum, I imagine they will engage with sufficient pedal pressure. But with half disc and half drum, then eventually the discs will be doing the work. Not good.

 

PRECISELY

 

A fellow Las Vegas local. I hope to meet you on the dusty trails out here.

 

Sorry for hijacking. It was, though, a natural progression wasn't it?

 

I'm in Phoenix.

 

Ah my bad. I thought I saw the Stratosphere in the distance.

 

Every set of drum brakes I've looked at in the last 20 years (not that many really) has been self adjusting.

[From Wikipedia] Automatic self-adjustment[edit]
As the brake linings wear, the shoes must travel a greater distance to reach the drum. When the distance reaches a certain point, a self-adjusting mechanism automatically reacts by adjusting the rest position of the shoes so that they are closer to the drum. Here, the adjusting lever rocks enough to advance the adjuster gear by one tooth. The adjuster has threads on it, like a bolt, so that it unscrews a little bit when it turns, lengthening to fill in the gap. When the brake shoes wear a little more, the adjuster can advance again, so it always keeps the shoes close to the drum. Typically the adjusters only operate when the vehicle is going in reverse and the brakes are engaged.

I don't have a 2nd gen, but since they sell a drum brake self adjuster repair kit, I'm going to assume they are self adjusting also.
http://www.partsgeek.com/gbproducts...lid=CKSRg_TU-scCFdgNgQodxUMDzw&ad=47433949212

I don't think the possibility of the axle seal failing is reason to avoid a certain type of brakes.

Debris in the brakes, I could go either way. I've seen problems with both.

Not a drum brake fan boy or Sweers apologist by any means. I was completely dismayed when I saw that the 3rd gen had drums in back. What the actual... I can totally imagine the meeting where this decision was made and I'm guessing that Sweers was not advocating for drums on the back. I'm no poker player or psychologist, but his answer to why they have drum brakes does not appear to be from the heart. I hope we got something in the trade-off. Maybe crawl control & MTS? I hope it wasn't just an extra 1/100000 of cent added to their stock price.

 

They don't self-adjust with normal driving. Period. No one drives in reverse enough to compensate for the brake applications going forward. Which is why it needs constant adjustment.

And that doesn't solve the other inherent issues with them

 

The main advantage of discs over drums is heat dissipation. Any situation where your vehicle stops frequently and hard, discs are better.

Drums are better parking brakes. The parking brake mechanism on drums is simple and the brakes are self-energizing. meaning that when the drum rotates, the shoes are wedged against the drum harder. Perfect for a parking brake.

In most driving situations in a light truck the rear brakes don't do a heck of a lot. In emergency stops the rear lifts up making the rear brakes pretty much useless so they don't heat up. In easy stopping there just isn't any heat build up. In either situation the advantage of a disc over a drum is moot.

The only time that rear brakes do matter is towing. And so the rear drums are spec'ed for a 3500 lb trailer, the max without trailer brakes. Again in this case the higher heat dissipation of discs is not an advantage. If you get to the point that you are overheating your rear brakes towing a trailer you are royally boned.

Toyota opted to keep the current system. And oversized parking brake that doubles as trailer brakes. A switch to discs would require more engineering effort but return no benefits. it wouldn't stop any faster or improve towing or payload so what would be the point?

 

1- better self-cleaning performance for off-road applications

2- cheaper and easier to service

3- (multiple experiences here) rear outer axle seal not leak in INTO drum and ruining drums and shoes

4- rear brakes always self-adjusted proper.


Those are the 4 main benefits of disc in this application. And I say this as someone who currently owns a 2nd gen with no plans to change out the rear drums. But the downsides are real and I'd have preferred they included disc, which is why on my 1st gen trail rig that didn't have any braking fanciness I swapped to disc and was all the better off for it

 

Appreciate Randonbob HalfWayThere, and Tubesock's comments. You guys may not agree, but at least you are giving reasons for your opinions. Other comments elsewhere on the site seem to hate drums simply because they are 'old' technology.

 

1, 2 3. No argument there.
4. The drums are SUPPOSED to adjust with the parking brake. I don't know how well it actually works, I've never bothered to check them.

 

You have done no such thing, sir. I was just trying to brake things up a bit, without drumming up any trouble, now crawling back to my hole...