Brakes. Why drums?

are they sealed good enough for extreme mud and off-road water and such??

 

I'm finding it hard to imagine how rear discs would be at any increased risk from rock/mud/debris damage. They live INSIDE the wheel. Any rocks kicked back from the front would encounter the tire first, not the brake disc.

We have rear drums for one simple reason: cost. Drums are cheaper to engineer and produce than a disc brake system. That leads to somewhat lower retails, but healthier margins for Toyota (or whomever is still using discs in the rear.)

If drums provided superior braking in harsh use, then I'd expect Baja Trophy Trucks and Protrucks to be running rear drums. Oddly enough, I see that they run 4 wheel discs. I can't really think of anything that would abuse, test or tax a braking system in harsh conditions more than the Baja 1000. Even Dakar Rally trucks use 4 wheel discs.

Kind of torpedoes the "rear drums are more durable in harsh environments" theory, yeah? As I said at the beginning, rear drums is solely based on cost. Toyota gets just enough performance from rear drums to still use them, so they do. They are certainly not better than disc setups.....

 

That would be the sensible thought for sure but the reality is the cross aiming from the fronts while turning and applying the brakes. It's the FR goofing up the BL and the FL goofing up the RR.

The easy proof is just look at a truck with rear disks and see for yourself. For the amount of braking force being applies by just the rear wheels it's not really worth the effort. Remember that idiotic park brake it needs then. Sill don't get rid of the drums they are still there only smaller.

 

I never noticed any damage to my rear discs on my 1996 Jeep Grand Cherokee when I had it....

I'm just not buying that the discs are inherently more susceptible to damage than drum brakes. I still maintain that the only reason that Toyota is putting rear drum brakes on Tacomas is purely economic: They can get the braking performance they need with drums, and save money in the process.

I'd like to have rear discs instead of drums, it would save quite a bit of weight actually. I even shaved 10 lbs per front corner on my BMW 335i when I swapped the stock discs and calipers for Alcon's with aluminum hat rotors and better calipers (even though the rotor was 10mm larger.)

 

From the factory? Or with those aluminum components you mentioned for your BMW? I saw the exact opposite in previous cars I ran, factory discs were about 10 pounds heavier than factory drums.

 

If the specs I found for the 2005+ rear drum are right, it weighs about 20.5 lbs. That's just the drum, not any of the other braking components. I can't find the same info for the front rotors though. So I guess it would depend on that. But yes, going from a one piece all steel rotor to a 2 piece aluminum/steel rotor on the BMW saved that much weight (disc to disc, not drum to disc obviously.)

 

Frontier's have rear disc's. I wonder if their board is filled with complaints about them. I can't imagine there is a lot of people saying they want the drums back. I think if the Tacoma had them everyone on this board would be saying they are great.

 

I think it depends what kind of roads you drive on. Where there is a lot of gravel roads you will see more people saying they wished they had rear drums instead. I've even heard people driving Dodge Trucks say that. The other thing is some people will not recognize what the damage was caused by so be none the wiser.

If I remember correctly my car that had disk brakes all the way round the rears where always in poorer shape then the fronts. That car was never on gravel roads, only that sand they put down in the winter.

 

You are absolutely right.

If I had sponsors and a pit crew and rebuilt my rig after every use, I would have discs for sure.

Unfortunately, down here on planet earth, car companies and owners don't get to live in such a single-purpose, cost-no-object environment. Sure, drums are probably cheaper (although I think I'd need that proven to me these days, discs being so common now). But they also happen to be sturdier than discs, and they are more than up to the task of braking at the rear of a 4500 lb pickup truck. Even the TRD brake kit doesn't offer an upgrade to the rear. These are the right tools for the job. On most trucks, rear discs are good marketing, not good engineering.

 

Rotors do shed the heat buildup much better, but our DD trucks usually don't see that much rear heat. Just not needed for the joe public pickup.

 

I drove hundreds of gravel fire road miles in my Rodeo and Trooper before that, both with rear disks, and never had a problem with rocks on either. My father-in-law put thousands of miles on oil well right-of-way roads and country gravel roads getting to them in a variety of (generally Ford) trucks with disks all around and never a problem picking up a rock. I'm sure it can happen, I just don't believe it happens often enough to influence which design to use.

I'm completely in the camp behind the only reason for rear drums being cost, pure and simple.

 

Yet here I have a 2010 truck that, according to the manual, has drum type brakes on the rear.


Thanks.[/quote]
These manuals help, don't they? Thanks God for them.
Take care
vbibi

 

Be careful about jumping to conclusions 'cause manufacturers take different approaches to how they bias braking action. VW's, for instance, are famous for wearing out rear brakes earlier in part because of how they are biased, in part because of the type of compound used.

 

I can't imagine how disks CAN'T be cheaper...they have so many fewer parts and assembly labor with all those springs and such must be a fraction that for drums.

BUT, for a heavy vehicle like a truck parking/emergency brakes must be much stronger than you can generate with a mechanical hand disk brake actuator...so they have small drum systems inside the top hat for the parking brake. That adds a lot of cost.

 

Drum brakes require MUCH less maintenence than the discs do. Repair costs are also much less. Let me give you a normal rundown:

Disc brakes: $50 pads, $80 rotors, $20 labor, plus the always probable calipers!
Drums: $40 for shoes, $20 spring and adjuster kit, $20 labor.

Discs need changed about every 35-40K Drums every 80K.

These are the average costs at the garage i work at so they maybe off from yours a bit seeing as how we only charge $40 an hour for labor. However i know what I'm talking about and drums make much more sense than discs just for the maint.

 

i disagree on all fronts here. respectfully of course. i love my tacoma and am very happy with it. and like someone else asked, what are you doing in a tacoma community anyway if youre so unhappy?

 

One would think from a mfg. standpoint that using the SAME materials across several different products would LOWER costs. So that being said, dump drums alltogether and source rear discs from another Toyota vehicle.

What is Toyota's line of reason? Who knows? 1.They have an inordinate number of drums in stock they need to get rid of. 2. They know the rear end of these Tacomas are too LIGHT so they are helping to weigh down the rear as cheaply as possible. 3. They stopped giving a shit about the Tacoma years ago and could care less.

On the case of 'Why drums?' I wish that I had a clear answer. Chevrolet and GM full size pickups went from drums (with discs on HD), to discs on all, back to drums (with discs on HD). I can remember the same thing with '95 model S-10s. My 95 S-10 SS had drums but my friends 95 ZR2 had discs (and OEM carbon fiber skid plates and driveshaft).

If you bought an Isuzu Rodeo you got drums UNLESS you opted to get 4WD then you got discs.

Jeep Rubicon: 4 wheel discs.

Seems like the consensus is leaning to 4 wheel drive with 4 wheel discs...

Let's face it, if Toyota made it an OPTION, how many of you would have ponied up and paid for rear discs? I certanly would have. On the other hand, if Toyota made it an option to have rear drums, how many of you would have ponied up for those?

Bottom line, Toyota needs to give in to menu options. In the short and long run they would make more money. I for one would have ordered my Tacoma with a TRD supercharger, TRD FJ rims, 4 wheel discs, etc. and paid a little on top for the security of warranty and factory vs. dealership installation concerns.

 

Your cost analysis is lacking.

Drums need turning every time...or replacing. Drums usually need new wheel cylinders...I've replaced far more wheel cylinders than I have calipers and since rear shoes on this truck are famous for lasting upwards of 70K you should plan on replacing them with the brake job. New shoes should be cut in to match the drum diameter or they will hot spot, glaze and maybe even warp the drum out of round and you'll have lock ups on hard stops. That's probably a reason a lot of people have what they call 'sensitive' ABS activation: it's really an out-of-round drum from crappy workmanship.

I know shops try to make disk brake jobs sound a lot more expensive and difficult but fact is most shops just slip out old pads and drop in new ones and call it done.

I've done brake jobs on both drums and disks for many years...since the days disks first came out on American cars. Disks are a lot easier and you can get away with crappy workmanship and they'll still work well enough. Bad workmanship on drums and you'll skid all over the road before you stop. IF you're stopped with the brakes at all.

You'd never find anyone putting drums on the front of a car today: considering the genuinely crummy workmanship in the majority of auto shops, they are a bona fide safety hazard waiting to happen.

 

Apparently unlike a couple of folks here, I actually drove the truck and read the literature and road tests before I spent my money. Car & Driver got 4 consecutive stops from 70 mph in less than 190 feet with no fade out of this truck. Between that and the memory of holding the crumbling remains of the rear rotors from my wife's MINI in a cardboard box, I think they were a good choice for the job.

What I don't get is how someone can be so exercised about this and have such a hate on for Toyota, and yet still give them their money.

 

I'm not complaining about my rear brakes...especially considering they are really just along for the ride. The front brakes do almost all the work in a truck, this one especially, and they are massively capable brakes. 4 piston dual-acting calipers over huge rotors. No wonder this truck stops so well and fade free.

I think the reason these people are so exercised about it is because, mostly, they are what ya' call enthusiasts. They bought the truck as much for looks as anything and man, a nice big caliper and rotor nestled in the opening of an aluminum wheel...maybe painted a color to match the front caliper and contrast the truck and wheel color....looks a hell of a lot nicer than drums. And a lot more modern and high-tech to boot.

Now THAT's an honest reason for disks I can get behind!