Diskbrakes on FF (1 Viewer)

[cody c]

I wanna see one that works .. coz I have my doubts ..

Here's the thing, the disc is before your diff, so it spins 4.11 (or 3.73, or 4.56 etc.) times faster than your hub/wheels. about 4 times the torque as at your wheels. Or, about 4 times stronger than it would be at your hub.

Somebody at the last "river shiver" told me about a friend who broke their t-case housing on a diesel crusier when they forgot they had their e-brake on and dropped the clutch in 4low.

The downfall, is that if you have open diffs, and one wheel on a slippery surface, you could have the vehicle slide, whereas with drum e-brakes both wheels are locked.

However with lockers and the vehicle in 4WD, it could lock all wheels.

The other option is a line lock, that would hold hydraulic pressure on your brakes, but that has its pros and cons as well. If your not familiar with this, you would apply and hold your brakes, then close a valve that would hold the pressure. The valve could be mechanically or electrically actuated.

 

[Tapage]

The other option is a line lock, that would hold hydraulic pressure on your brakes, but that has its pros and cons as well. If your not familiar with this, you would apply and hold your brakes, then close a valve that would hold the pressure. The valve could be mechanically or electrically actuated.

I've been debating the like lock solution for a while .. but I'm more prone to the t-case mechanical route .. just wanna be sure that works ..

 

[cody c]

I've been debating the like lock solution for a while .. but I'm more prone to the t-case mechanical route .. just wanna be sure that works ..

would be nice if you could get an electric lock/valve that would open upon energization (key on) and have a one way valve in parallel to the valve.

That way, you turn on the vehicle and any residual pressure release, when you turn it off, you press the pedal to the floor and the one way valve allows you to pressurize the hydraulics (brakes on) and then retains it.


with my 80 i have the cummins and the 5 speed, so I dont notice the e-brake on till it starts to smell, and leave it in gear when parked...

 

[Elbert]

line loc is not an emergencey brake....it your hydraulic system fails so does the line loc.

Line loc will certainly loc the brakes but its a hydraulic device...where as emergencey brakes are mechanical and only act on the rear.

Some of the old school 2.5 ton trucks had a emergencey brake that was part of the drive shaft or flange. I think thogse were drom setups but they worked

that the big deal with going to 4wheel disks to me...for one better brakes part two.... emergencey brake considerations.

 

[Elbert]

I used a HZJ73 rear axle with OE disc brakes. I don't know where you're from, but in my case it was the quickest, cheapest and easiest solution. I traded in my drumbrake rear axle (in need of a brakejob), paid 100 euros and took the HZJ axle with me. All i needed to do was to reweld the spring perches and put an adjustable proportioning valve in the brakeline.

If you're in Europe, this might be a good solution.
Works like a charm too!

don't thnk there is any such animal over here in the US...maybe Canada? If so it would probally cost a premium if ever able to find one.

 

[mustardfj40]

don't thnk there is any such animal over here in the US...maybe Canada? If so it would probally cost a premium if ever able to find one.

A local cruiserhead imported some of these puppies into the US from Aussie, all I remembered is they use floating brake calipers since I helped him move these axles around. Pretty cool if you can find them. He probably still have some of these rear FF floaters stashed somewhere

Btw, that was my FF disk swap write-up. So far, I am very happy with it. It was easy and used all Toyota parts that can be found relatively easy in US.

 

[serenity]

Here's the thing, the disc is before your diff, so it spins 4.11 (or 3.73, or 4.56 etc.) times faster than your hub/wheels. about 4 times the torque as at your wheels. Or, about 4 times stronger than it would be at your hub.

It's actually the opposite, it spins 4.11 times faster but the torque will be 4.11 times lower. Meaning that it won't have to be as strong, although I still don't like the fact that the caliper bracket only bolts around the output shaft cone. If I bought one of their kits I would still weld on an extra arm that extends out and bolts another area of the transfer case to help counter-act the torque.

 

[Mark W]

To the OP... those brackets bolted on. (They are made by sacrificing a set of OEM knuckle housings). I have done this a couple of times and LOVE the results. All Toyota parts, and with 4runner calipers front and rear I can lock up the 39.5x18 Boggers under my '40 on dry pavement.


Mark...

 

[Mark W]

line loc is not an emergencey brake....it your hydraulic system fails so does the line loc.

Line loc will certainly loc the brakes but its a hydraulic device...where as emergencey brakes are mechanical and only act on the rear.

Some of the old school 2.5 ton trucks had a emergencey brake that was part of the drive shaft or flange. I think thogse were drom setups but they worked

that the big deal with going to 4wheel disks to me...for one better brakes part two.... emergencey brake considerations.

Does anyone really consider the OEM parking brake on the back of the transfer case an "emergency brake"? Or for that matter, does anyone think that the parking brake arrangement on the rear wheels of the later rigs is even AS effective as simply slamming the tranny in a lower gear and eventually turning off the key?

The whole "it is not an *Emergency brake" argument is meritless IMHO when we are talking about Cruisers.


Mark...

 

[Elbert]

when you have to stop on a very steep grade....parking brake / emergencey brake... becomes fairly important. Just trying to hold position which I know a line loc would do very well.

I want something that works and so it does matter to me if one understands if its a mechanical device or hydraulic and how it works and if it operates independiatly of the hydraulic system.

so what happens when your engine is off and you are out of the vehicle.. quasi flat ground is not an issue.... steep grades or other places similar are.

You have your view and I have mine.... I'm not in an argument, I made a simple statement.... if you don't agree that's fine with me.

 

[Mark W]

Not arguing about anything here. just pointing out that those who point to the fact that line locks can not be used in an "emergency" to stop the vehicle if the hydraulic system fails, are usually overlooking the fact that the factory mechanical parking brakes are far from suitable for doing that job as well. So (in my view) loss of this mechanical parking brake is not really of any concern.

Considering how many of the factory parking brakes actually are in good working condition and adjustment, I would wager that an awful lot of those same people advancing that argument more likely than not could not keep their rig anchored in a steep suburban driveway using their parking brake alone.

When I compare that to the number of sudden failures of the service brakes that I have seen over the years... I am more than comfortable with the use of line locks as opposed to the OEM mechanical parking brakes


Mark...

 

[serenity]

Not arguing about anything here. just pointing out that those who point to the fact that line locks can not be used in an "emergency" to stop the vehicle if the hydraulic system fails, are usually overlooking the fact that the factory mechanical parking brakes are far from suitable for doing that job as well. So (in my view) loss of this mechanical parking brake is not really of any concern.

Considering how many of the factory parking brakes actually are in good working condition and adjustment, I would wager that an awful lot of those same people advancing that argument more likely than not could not keep their rig anchored in a steep suburban driveway using their parking brake alone.

When I compare that to the number of sudden failures of the service brakes that I have seen over the years... I am more than comfortable with the use of line locks as opposed to the OEM mechanical parking brakes

Mark...

I've only seen brakes fail firsthand once, on a mates rig. He was changing gears at the top of a steep but short decent, put his foot on the brake while dropping from 2nd to 1st and the hard-line blew out. His rig built up too much speed too quickly for him to get it into a gear (worn synchros) and he didn't even get time to go for the park brake. He speared into a ditch did a quite impressive nose stand and bent just about everything related to the front axle.

Moral of that story is s*** happens quick and don't buy an old poorly maintained rover.

As for the factory handbrake on my 80 series. I had it rebuilt a few months back. It holds ok on hills now but I can still drive down the road with it on and not notice it. Still better to drop a gear or 2 in an emergency than use that piece of crap.

As long as your line lock and the rest of your brake system is well built and maintained it shouldn't fail, and it should work better than the original cable setup.

That said I'm still doing a cable brake on my project thanks to our ridiculously strict road rules.

 

[canadian bum]

Anyone have a link to the thread mentioned with using front knuckles to make rear discs? Very interested in that and I even have parts kicking around to do it. The original link doesn't work, which is why I'm asking.

 

[dr_claw]

your welcome

 

[dr_claw]

 

[Isotel]

Dan the Man, just released a pretty cool new bracket that fits into this thread nice!

Axle Flange, Rear, Toyota, Full Float - RuffStuff Specialties

 

[Cruisertime]

Looks like Dan and Co are getting a call tomorrow.

 

[dr_claw]

Interesting,

Ruffstuff weld on brackets + Longfield 30 spine shafts is only a little more than the polyperformance Semi Floater rear shafts.


Hmmmmmmmmmmmmmmmmmmmmmmmm......