If that isn't the best line in this whole thread I don't know anything.

Come to think of it, my '99 Nissan Maxima has rear disks with caliper actuated e-brakes. They are so bad that I frequently drive off without releasing the brake and don't even tnotice the brake is applied. -- Matt

The axle walks in and out. This motion is perpendicular to the driveshaft(not trying to dumb it down, I just wanted to be clear to all) This motion pushes the pistons into their bores(a little) When you press your brake pedal it takes a little fluid to take up the slack. Calipers have large bores, so it takes more fluid to move the piston a given distance but at a greater mechanical advantage. This isn't a problem on the front because the front wheel bearings keep the discs at pretty much a static distance from the caliper. It doesn't matter too much that the chev calipers float. A full floater kit uses the same type of hub locating wheel bearings that the front does. Residual valves keep fluid in the calipers after you press the brakes. They can be bought with different holding pressures and yes the do cause a little drag. If anyone has a comment about my post feel free. <img src="/forums/images/graemlins/smile.gif" alt="" />

anyone have any idea how much the axles walk? (Ill check my manual for a spec) If so I can compare that spec to the Chevys. I hate using Chevy stuff since Im not familiar with it but I know a few guys that use the caty calipers for the rear conversions on Mustangs and they are happy with them even though the Ford 8.8 uses C clip axles. I am also very happy with the SN 95 rear disc all around and The E brake holds better than the cable did with less effort. They are not real expensive but they use a solid non vented rotor (thiner than an vented) That would be hard to convert. They require a special tool to spin and press them back in durring brake changes but its cheap.

Here is someting interesting, Looking through my Toy manual I see the land cruiser was available with a rear disc. It does not say what year though. Do the LC s use the same diff or backing plate setup? A quick serch on Ebay found cruiser disc kits selling with some good info. Looks like the same Chevy setup Im considering less park brake callipers.
http://cgi.ebay.com/ebaymotors/Rear...itemZ300085372835QQrdZ1QQsspagenameZWDVW
FAQs
Will I need a proportioning valve? Maybe, there is no clear cut answer here because of tire size, vehicle weight, brake master, etc. We do suggest removing the residual valve and test. If you have premature rear lock up, then a proportioning valve may be the cure.

Do I have to remove the axle shafts? Yes and no. If you are very crafty with a saw or torch then you may be able to cut the backing plate off without damaging the axle housing or seal. Otherwise you simply remove the rear inspection cover, take out the spider gears and clips. The axle will slide out then.

What position are the calipers? Installers choice. Because of different spring configurations, we have seen various position people have located the caliper. As long as you have ample room to attach the brake line and the bleeder is up, you are fine.

Where do the spacers go? In between the axle housing flange and the backing plate. This insures proper alignment of the caliper.

What kind of parts are these? They are remanufactured loaded GM calipers, and milled GM truck rotors. The backing plate and lines are custom made.

I want to keep my Land Cruiser all Toyota, can I use Toyota calipers? No, while everyone sees the advantage to Toyota parts, their drum brake system is moderate at best. This set up has stopped thousands of GM cars and trucks.

Can I use this on a full floating axle? No, these brackets are designed for a semi-floating axle. That is what all FJ40's sold in America had.

Can I use my wheels? The vast majority will fit without any problems. Rarely, some thick walled aluminum rims may get close.
I think Ill go ahead and get the Sky brakcets and rotors and sorce my own calipers and brake lines and give it a shot. If Im not happy with the E brake Ill go with a drive shaft one from there and sell the rear e brake callipers for front ones to help cover the cost of the DS brake kit. Either way Ill be better off then I am now..... I hope <img src="/forums/images/graemlins/scared.gif" alt="" />

I dont think toyota axles move at all. They are bolted to the housing and they have a press fit bearing and retainer to keep it all tight. It what c clip eleminators use for chevy axles.

Correct.

The Landcruiser kit won't work on mini because the axle housing ends (bolt pattern) are different. That kit isn't much different from Sky's kit anyway.

Yes, the semi-floating axle does walk in and out a bit. Worse as the bearings wear of course. I'm pretty sure the FSM has a spec for how much play is allowed. Full-floating hubs don't walk because the tapered roller bearings are preloaded against each other. However, lots of people run disks w/ semi-floaters with success, so it must not be THAT big of a problem.

Disk brakes have a WORSE mechanical advantage compared to drums because the drums are self-actuating, as was mentioned above. They requre both more fluid and more pressure. The manual prop valve is needed to increase the pressure to the disks compared to what the drums needed (and for tuning).

Residual valves can be used to help two things- they can help keep slight pressure on the pads so that they aren't pushed back into their bores as easily when the axle walks (as was mentioned), and they also help to "preload" the seals, which means they don't need as much initial fluid to start doing the work (improves pedal travel/feel). Its kind of a bandaid fix, but it seem to help.

There are some aftermarket rear disk kits that use a mini-drum e-brake in the rotor hat like some of the OEM's do. I'm sure they're expensive so I haven't looked into them much to see if there is an application for a Toy.

trying jacking up the rear of your truck and grabbing the tire on the top and bottom and try to move it in and out. on mine i can move my tire in and out quite a bit(not sure about measurements). it could be b/c my bearings are a bit worn, but i doubt it.

i also doubt that you are going to be able to effectively do a rear disc swap for less than $500. from the price of the brackets, calipers, rotors, adj. rear proportioning valve, and larger master cylinder to compensate for the increased pedal travel. its going to be expensive.

and honestly, if your wife or girlfriend is anything like mine, you probably care about the "brake" problem w/ her truck a lot more than she does and she won't care, or know if she has disc or drum brakes. let alone a turbo charger. but everyone is different haha.

I found that when I swaped from drums to disc the stock master cyl was fine. Thats for a singe piston rear disc brake. Looking at the surface area of the single piston and the bore and longer stroke of the drum cyls it ended up about a wash on that car. I dont expect to need a larger master cyl, I do expect to maybe need a prop valve maybe a resi act too but Ill add them if needed but these kits and calipers are made for semi float axles so I expect it to go smooth. Summit has a nice prop valve for under $70 if I recall. Im going to TRY to do it for under $500 so stay tuned. I may have already found a set of calipers for free from a budy so thats a big savings right there.
I spoke with sky and they said you can al la cart any of there parts no problem. We are leaving for some hard earned vacation tonight and the little lady is into me on that as is so Im not sure when she will start provisiong fundage for this project, I have been known to spot some here and there <img src="/forums/images/graemlins/wink.gif" alt="" /> and her B day is the 18th so I think I can get this ready to go on some time in April if not sooner.
JG