MTL_4runner

I was looking into this because I hate dealing with my drums...adjusting them, not very impressive stopping power and they tend to rub if they are adjusted for a firm pedal.

Now I know you guys are going to start telling me about all the front brake improvements I can do but what I would really like is to hear about any rear brake swaps you have seen?

Anyone?

Flygtenstein

Front Range Off-Road Fabrication.

Early 80's Supra disks and you get a free floating rear out of it.

I don't have it, but that is one of the only games in town.

Jeff the marmot

Here's the link and look about halfway down the page:
http://www.frontrangeoffroadfab.com/floater.htm
But did you notice that he also lists 8 things that you need to find mostly out of a junk yard to complete the "kit"? That's not how I want to spend my weekends. It does look intriguing, though. It does include an e-brake. It doesn't mention anything about it's affect (if any) on an ABS sensor.

He also doesn't mention anything about what years of Toyota 8" rear axles that the product/conglomeration should work with. 'Course maybe no 3rd gen 4Runners have tried it yet, although it should be the same as a Tacoma.

MTL_4runner

I am really surprised that no one offers a kit to just bolt on a set of cheap calipers (maybe chevy or toyota single piston) and then just give you a machined flange with the correct spacing and pattern to bolt onto the axle like the one in this kit for Suzukis from www.spidertrax.com :



Or maybe a kit like this might work:

http://www.allprooffroad.com/brake.html

Seems like it would be quite easy but maybe there is something I am missing so I won't jump to any conclusions. I think the e-brake could be done with a simple line lock:



I read that an axle mounted lever brake sucks!
http://4-low.com/tech/parking_brake/

Maybe one with a mechanical lever on the piston would work like this:


Do you really need full floating axles or can you just get away with a residual valve....I can't imagine the axles having that much play....anyone know anything about this?

Anyone know why most trucks come with rear drum brakes from the factory anyway and why all the sedans seem to have discs all the way around?

mtnbkr

I imagine it's because you don't want too much pucker power back there due to lockups. Especially when you have an empty bed. Even with drums, pickups tend to lock up easier in the rear. It's less an issue with SUVs though.

I'd rather have discs and a good proportioning valve. Drums are a PITA to work on. Too many springs and clips...

Chris

Shane

Yes, it did indeed suck. Other people have it and claim no problems, but as always YMMV.

There's lots of different disc kits available for the earlier rigs, Some of which should work on the new rigs no problem. Others will have to be updated, the FROR kit will probably need a new version of the shafts to fit the length needed if it's changed from the earlier axles. Here's some pictures of mine, it works pretty good but I'm finding there's a good amount of brake fade from the solid rotors. I have a steep driveway and if I ride the brakes down the last hill I can't get the parking brake on tight enough to hold the truck, but if I engine brake then it holds great. Probably just needs more leverage on the cable...

MTL_4runner

Shane you did a really kick ass job on yours....it really looks great!

It looks like we are talking major $$$$$$ to do what you did....did it?

Shane

Thanks. I've got a pretty good chunk of change in that axle, It's not that bad though. It's only money, right? Got a deal on a complete axle so I was able to take my time and clean it up good without putting my truck out of service.

MTL_4runner

Will the axle off of an LandCruiser work as a direct swap too?
I think they have disc all around......anyone know?

Flygtenstein

The reason there is a spindle, hubs and the like is because you get a full floating rear axle out of it.

That way when an axle shaft goes, it is easier to change and be stronger before it busts. That is necessary instead of just a bracket because otherwise the rotors walk in and out when it is semi-float.

As Jeff said, there is a lot of other stuff, some of which will not be off the shelf, but if you want discs, this is how to play the game.

MTL_4runner

Is this only when you are a serious off roader or does this happen in street driving too?

I would think that a residual valve would take care of this floating problem by keeping the calipers on the rotor wherever it floats (all calipers have large compensation for rotor runout so if they are true then it should work for axle float too)....maybe not?

rimpainter.com

For a SUV, the 4Runner stops really well. In fact, it will out-stop a lot of cars out there.

I am just curious why you want to screw with this?

Dont get me wrong, it would be cool to have rear discs - but pretty expensive and labor intensive...for what gain?

Shane

Drums fill with mud and water and become ineffective, disks tend to have more stopping power for bigger tires.


The rotor movement on a semi-floater axle is minor, and can be pretty much solved by using a residual valve to help keep the pistons from retracting.

Praufet

Is there not some way you could do it your self with junkyard parts? And while we're on the subject of brakes, would there be a way to swap out the front calipers with larger calipers from another model of toyota?

MTL_4runner

Thanks Shane, that is kinda what I thought.

I am tired or adjusting the drum brakes and would welcome better stopping power especially with the trailers I tow (boat, jetskis, snowmobiles......yada yada) where the weight in the back seems to force the front to do all the work. I have even warped a few pairs of front rotors from just that situation.

It seems like it should be alot easier and cheaper than the sites I have seen charging $500-$600 per kit. As far as I can tell you should need a caliper mounting bracket, pair or calipers, pads, rotors machined to fit where the current drums fit (ie enlarging the centers slightly), some new solid brake line (select aproprite length and bend to approximate original placement) or braided stainless line and that should about do it. The residual valve is recommended but optional and something will need to be done about the e-brake....I like the Hurst electronic line lock style but maybe the axle mounted one might work with a longer throw on the lever (because the pads seem to wear quick when in close proxmity to the disc surface).

Am I way off on my assumptions?

Shane

Yes, but you likely already have the larger calipers. Pre-95 IFS trucks and runners had two (IIRC) different front calipers, either with 2 big and 2 small pistons, or all 4 big. Pre-85 trucks and runners can be upgraded from their non-vented rotors and calipers to the newer calipers by using '83 FJ40 vented rotors. At some point the big calipers became standard, I'm pretty sure your '94 already has them.

If you're having to adjust them manually they're either assembled wrong, dirty, or you need to start using the parking brake. The stock parking brake system is also the means for adjusting the drums automatically. The rear drums are still an excellent system when properly maintained. You can raise the proportioning valve's rod (attached to the axle) a bit to increase the rear braking bias.
Electric line locks are not parking brakes, no matter what the manufacturer claims. They do not have a 100% duty cycle so they'll burn out after a while, and if power is lost so is the pressure. Some have used manual line locks but they can leak down over time. The AllPro e-brake is not axle mounted if that's the one you're talking about, it mounts to the older style transfercases so without swapping out your transfercase you won't be able to use it anyways.

Toyota brake hard lines use a double inverted flare, so make sure that you have the proper tooling to make these if you decide to make your own hard lines. Regular 3/16" brake line will work fine in place of the stock metric line.

Shane

Just to clarify on this, no the residual is not 100% necessary. Without it you should expect a little more pedal travel. Worst case your rear bearings are shot and allowing the axle shaft to move too much, and in that situation I think it's pretty obvious what needs to be done.

The fact that it's a full-floater gives no benefit when changing out a busted shaft. If it breaks at the hub end you still have to pull the bracket to get the rest out, and if it breaks at the diff end you still have to pull the diff to get the leftovers out of it. It's theoretically stronger, but stock rear shafts don't break that often. The biggest problem the rock crawling guys have with the FROR kit is shearing off the hub's mounting studs. The trail fix for this is not pretty if you can't get a hub bolted back on it securely.


Honestly, my opinion after setting up FROR's kit, unless you have a glaring need for the full-floater (like flat towing without spinning the drivetrain) go for one of the other kits that uses the stock shafts and that'll give you vented discs and an integral parking brake. There is no "perfect" kit out there, they all require a little fabrication or modification to work good. It's a good kit, it's cool, but it's also not necessary.

Shane

To expand this thread even further, you can also look into swapping out the master cylinder for one with a bigger bore in order to move more fluid which will give you a firmer pedal. Then if your stock booster is a single diaphragm (older rigs), swap in a dual-diaphragm booster to get more assist which will cover the increased effort needed for the larger master.

Look for 4RnrRick's post in this thread for a comparason picture

HaveBlue

ORS also has a break conversion I'm kind of interested in.

MTL_4runner

That is almost exactly what kind of a kit I was looking for!!!
Doesn't have any prices on it either....which scares me a bit.

Anyone done anything like this on a 3rd gen 4runner?