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ianacole
04-25-2011, 12:53 PM
Greetings all! I'm looking to upgrade the stock brakes on the '84 Mini Truck axle in my FJ. I've reviewed a bunch of different threads on Mud and the interwebs, and have some questions hopefully someone smarter than I can answer. Here's the thread I'm using for reference: http://forum.ih8mud.com/79-95-toyota-truck-tech/169161-vented-rotor-swap-easy-pie.html

Questions:

In the thread it lists these parts as being needed:
Front calipers off 89 4runner with 22re
89 4runner 22re pads
1984 FJ60 rotors
Bearing Seals
Bearing Grease

Are these the right seals? http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Axle-Seal-Beck-Arnley_18020393-P_374_R|GRP60007_228382889____

Anything else I should consider as part of this upgrade since I'll be pulling the hub and brake assemblies?

Thanks!

Ian

leiniesred
04-25-2011, 01:39 PM
I have a 1985 mini truck front axle with the (original) S12W calipers from my 1989 V6 4runner and a pair of napa 1984 FJ60 vented rotors...But there is one more part on mine too. I have a spacer between the top hat and the brake rotor to move the rotor INBOARD. My brakes bolt up to the same side of the ears this way. I do not have any dust shields on the knuckles. Just a spacer. I've had this setup for at least 6 years.

rover67
04-25-2011, 01:55 PM
I have the S13WB calipers on my 60 with stock 85Fj60 Rotors. The rotors are thin for the calipers (20mm) but they work. Anybody know of a thicker rotor that fits the same applications?

Looking for a 25mm thick rotor.

Also, in your linked post Dave, it states that going to a bigger master will result in softer pedal feel, this is backwards... bigger masters make the pedal stiffer. Also, in the linked post you state that the later 80 series MC's have a residual pressure valve for the disks... it's the other way around.. drum masters have the residual pressure valve for the drums.

Using a MC without the residual pressure valve will result in a pedal that has more travel or has to be pumped to get the wheel cylinders in the drums back out to their operating position. If the MC that you got is for 4 wheel disks you have to buy a residual pressure valve from someplace like summit and plumb it inline with the rears.

ianacole
04-25-2011, 02:02 PM
Thanks for the responses. As you can surmise, I'm trying to get better braking for the FJ40 ('73). Currently it has the '84 axle up front with the stock '84 brake system, stock drums in the rear, and a GM MC.

DaveInDenver
04-25-2011, 02:49 PM
Also, in your linked post Dave, it states that going to a bigger master will result in softer pedal feel, this is backwards... bigger masters make the pedal stiffer.
Didn't in my case, when I put in a new 1-1/16" master from a 1994 4Runner my pedal got softer (it stopped but not break-your-nose strong and felt weird soft) with no other changes (stock S12W calipers, 10" drums, 1" booster, stainless hoses). Went back to the correct (used) 1" M/C and pedal feel returned. Shrug, maybe it's a booster mismatch or some other problem, like trapped air? Would not surprise me to find that my bucket of rust has other issues. I came *this* close to driving it off a cliff this weekend. I hate old crap, would be nice if we just had one f'n vehicle that I didn't have to work on. Turns out that my M/C seems to be failing /again/, so I may get to try this experiment another time. I will remove that statement from the post.
Also, in the linked post you state that the later 80 series MC's have a residual pressure valve for the disks... it's the other way around.. drum masters have the residual pressure valve for the drums.

Using a MC without the residual pressure valve will result in a pedal that has more travel or has to be pumped to get the wheel cylinders in the drums back out to their operating position. If the MC that you got is for 4 wheel disks you have to buy a residual pressure valve from someplace like summit and plumb it inline with the rears.
OK. I was just parroting what Marlin told me that of the two main non-ABS 1" M/C options, the FJ80 part has two residual valves, the Hilux unit (which never got rear disc brakes) doesn't. The explanation was that disc calipers require more volume but less pressure and have no lining wear compensation, so using a M/C without residual valves would mean the pedal has to travel further before the pads meet the rotor, thus the need for two residual pressure valves. IOW, the FJ80 M/C was sorta universal in that it would work with drums or brakes (with maybe different pedal feels?), whereas the Hilux unit would need an external valve to run rear discs.

rover67
04-25-2011, 04:02 PM
Didn't in my case, when I put in a new 1-1/16" master from a 1994 4Runner my pedal got softer (it stopped but not break-your-nose strong and felt weird soft) with no other changes (stock S12W calipers, 11" drums, 1" booster, stainless hoses). Went back to the correct (used) 1" M/C and pedal feel returned. Shrug, maybe it's a booster mismatch or some other problem, like trapped air? Would not surprise me to find that my bucket of rust has other issues. I came *this* close to driving it off a cliff this weekend. I hate old crap, would be nice if we just had one f'n vehicle that I didn't have to work on. Turns out that my M/C seems to be failing /again/, so I may get to try this experiment another time. I will remove that statement from the post. Weird... hydraulically (mechanically), the bigger MC has less advantage over the calipers, so it takes more pedal pressure and *should* result in harder pedal feel. a smaller MC would have to move farther to move the same volume and have more advantage thus creating a situation where the brakes might feel a big softer. I am actually switching to a bigger MC today from my stock 60 one so well see if it actually works that way in my case.



OK. I was just parroting what Marlin told me that of the two main non-ABS 1" M/C options, the FJ80 part has two residual valves, the Hilux unit (which never got rear disc brakes) doesn't. The explanation was that disc calipers require more volume but less pressure and have no lining wear compensation, so using a M/C without residual valves would mean the pedal has to travel further before the pads meet the rotor, thus the need for two residual pressure valves. IOW, the FJ80 M/C was sorta universal in that it would work with drums or brakes (with maybe different pedal feels?), whereas the Hilux unit would need an external valve to run rear discs.

Interesting.. Well, I bet Marlin knows the correct thing here :) I was under the impression that the residual pressure valves were for the drum brakes and were only on drum brake MC's. I hope I get one in the T100MC I am putting in today!

nuclearlemon
04-25-2011, 06:38 PM
the residual valve is for drum brakes. it's to keep some light hydraulic pressure on the wheel cylinders, they are found inside the master cylinder where the line hooks up.

the proportioning valve is external to the master cylinder and it's to adjust the amount of hydraulic pressure between the front and rear in a drum/disc setup

DaveInDenver
04-25-2011, 07:37 PM
:-S

Marlin Crawler: Big Bore FJ80 Brake Master Cylinder (http://www.marlincrawler.com/brake/master-cylinder/big-bore-fj80-brake-master-cylinder)
This is a genuine Toyota 1990-97 FJ80 Land Cruiser Brake Master Cylinder. This fits all FJ80 Land Cruisers and also makes for a great replacement part for older Pickup's and 4Runners that have a smaller bore. Aside from the FJ80, it also fits 1979-1995 Pickups/4Runners. Features 1" piston and residual valves for both front and rear. Works with both drum and disc brakes. Bolt on installation. Includes reservoir. On 1979-1985 Trucks and 4Runners the smaller factory bore works fine with stock, solid front rotors and 8" rear drums. If you upgrade the rear to larger 1986 and up, 10" drums and/or upgrade the front to a vented style caliper you will want to install a 1" bore master cylinder like this one for additional volume.

Upgrading your brakes without changing the master cylinder results in excess brake pedal travel. If you have upgraded your brakes on a 1979 to 1985 truck and now you have to push the peddle nearly to the floor, this master cylinder will make the peddle feel like it should.

Please note: In the picture above, the left outlet port operates the front brakes, and the right outlet port operates the rear brakes. Just remember, the front port (furthest from the booster) works the front, and the rear port (closest to the booster) works the rear brakes.

Marlin Crawler: Big Bore V6 Hilux Brake Master Cylinder (http://www.marlincrawler.com/brake/master-cylinder/big-bore-v6-hilux-brake-master-cylinder)
Replacement master cylinder for older Pickup's and 4Runners with a smaller master cylinder. Fits 1979-1995 Pickup/4Runner. Features 1" piston. Works with drum rear brakes. Bolt on installation. Includes reservoir. On 1979-1985 Trucks and 4Runners the smaller factory bore works fine with stock, solid front rotors and 8" rear drums. If you upgrade the rear to larger 1986 and up, 10" drums and/or upgrade the front to a vented style caliper you will want to install a 1" bore master cylinder like this one for additional volume.

Upgrading your brakes without changing the master cylinder results in excess brake pedal travel. If you have upgraded your brakes on a 1979 to 1985 truck and now you have to push the peddle nearly to the floor, this master cylinder will make the peddle feel like it should.

Please note: In the picture above, the left outlet port operates the front brakes, and the right outlet port operates the rear brakes. Just remember, the front port (furthest from the booster) works the front, and the rear port (closest to the booster) works the rear brakes.

nuclearlemon
04-25-2011, 07:47 PM
http://www.thebrakeman.com/valvetechi

We may as well start with the residual valve, because it is the first one that should be determined whether or not it is needed. This valve does exactly as its name suggests. It keeps a pre-determined amount of residual pressure in the line after you remove your foot from the brake pedal. This aids in preventing excessive pedal travel as well as insuring consistent height to the pedal. In a drum brake, heavy return springs are present to pull the shoes away from the drums. When not in use, the shoes are pulled back until they rest on a centering pin, usually located at the 12:00, or top position, on the backing plate also holding the wheel cylinder. In order to avoid the excessive pedal travel to move enough fluid from the master to activate the shoes, a 10-12 pound residual valve is installed in the line. Sine the return springs are stronger than the 12 pound valve, the shoes are pulled away from the drum in spite of the resistance so no brake drag results

A disc brake system, however, cannot tolerate this kind of pressure, as it would cause the pad to rub the rotor even when your foot was off the brake pedal. 10-12 pounds of line pressure on a disc brake will cause detrimental drag and a tremendous decrease in pad life. Worse yet, if the vehicle is driven at a consistent speed, the temperature will climb, due to this drag. This will cause the pads, rotors and brake fluid to swell causing lockup. At that point, the only way the brake system will release is for everything to cool back down.

DaveInDenver
04-25-2011, 08:04 PM
That makes sense Ige and is consistent with Marco. So is Marlin's description wrong? I'm just really confused. Also, what then is the purpose of ~2 lbs residual valves that are used on hot rod disc brakes?

rover67
04-25-2011, 10:19 PM
Man, that's even weirder.

I stripped the threads on the T100 MC I was installing tonight so no test drive :( I'm a bone head.

L43dean
04-25-2011, 10:25 PM
Dave, your not the only one. Are we talking about a 73' Fj-40 with an entire Hi-Lux front axle? Or Hi-Lux disc brakes installed on a Cruiser axle, front or rear?

Red_Chili
04-26-2011, 07:41 AM
V6 IFS calipers on FJ60 rotors
FZJ80 MC
V6 vacuum booster
In my case, SA front calipers and disks in the rear, but not really required
Front Range Offroad Fabrication modified Summit Racing proportioning valve

All the above (rear disks optional) are well integrated and will stop you NOW. I tried the incremental approach and was not happy until the Full Meal Deal.
HTH,

ianacole
04-26-2011, 07:54 AM
Dave, your not the only one. Are we talking about a 73' Fj-40 with an entire Hi-Lux front axle? Or Hi-Lux disc brakes installed on a Cruiser axle, front or rear?

Full Hi-Lux axle, front.

L43dean
04-26-2011, 10:08 AM
Full Hi-Lux axle, front.

Got it! Thank you. What size wheels are you trying to stop?

ianacole
04-26-2011, 10:20 AM
37", on 16" wheels. Not sure if some of the available options have specific wheel size requirements.

leiniesred
04-26-2011, 10:35 AM
I can't lock up my 37x12.50 R15 Iroks on dry pavement with my original 1989 calipers, booster, master cylinder, stock rear drums, fj60 rotors.

It sure sounds cool and the pitch angle change is pretty amazing when I try though.

Red_Chili
04-26-2011, 10:40 AM
The setup I described above will do that VERY nicely. The howl from four locked 35" MT/Rs definitely has an instructive effect on errant compact car drivers. ;-)

DaveInDenver
04-26-2011, 10:42 AM
The setup I described above will do that VERY nicely.
He's already got S12W calipers and booster. He should also have a 1" master cylinder. Proportioning valve, that probably keeps the fronts working. I also really wonder what's the story with the FJ80 master, there's got to be something about it. I'm tempted to try it to replace my worn one, but am still unsure on the details with the rear circuit and drums. Marlin says it'll work with either, but what Ige and Marco say also makes sense and I don't want my rear return springs causing my pedal to go to the floor.

There is nothing special about the V6 calipers unless they're from a 1992-1995 4Runner, which are S13WB castings. The only difference would be a 1988 V6, which got S12W and the 22R trucks got 12+8 calipers. In 1989 Toyota started giving all 4WD trucks the same calipers, master and booster until the 4Runner got the upgrade in 1992. The only differences would be if the truck had ABS.

Red_Chili
04-26-2011, 10:50 AM
Whichever ones I have, from my 1990 V6 3.0 RC1, had more fluid capacity than the stock 1987 I4 calipers. FWIW.

Brian from FRORF thought the whole hullabaloo on the FZJ masters residual valve was untrue... because of near zero runout of Toyota rear disks. Dunno. Mine from Marlin works mah -velously.

ianacole
04-26-2011, 11:02 AM
The setup I described above will do that VERY nicely. The howl from four locked 35" MT/Rs definitely has an instructive effect on errant compact car drivers. ;-)

Was that setup pretty close to bolt-on? How squirmy is your truck under braking?

Red_Chili
04-26-2011, 11:58 AM
Was that setup pretty close to bolt-on? How squirmy is your truck under braking?
The fronts and MC etc. were bolt on. So were the rears but they required green lube ($$$$$) :lmao:. The truck is very stable. Mind you, I have a longer wheelbase which helps.

Springs and bushings would become more important I think, with both 'go' and 'stop going' enhancements.

ianacole
04-26-2011, 12:24 PM
Interesting...Advance Auto Parts show the same part number for the calipers whether I pick the '89 4runner 3.0 or 22REC motors.

Red_Chili
04-26-2011, 01:29 PM
They probably picked one in the interest of inventory... gopher it!

Air Randy
04-27-2011, 02:04 PM
Why are you trying to upgrade what you already have? Does it not stop good or what? Just curious.

Changing out brakes on a 40 can be a slippery slope. Going to the mini truck disc setup you already have is an easy conversion and works well. If you decide to go with rear discs there are a lot of bolt on kits out there but then you start to run into proportioning issues. I have the Monte Carlo rear discs and even if I run 2 proportioning valves in series, I cannot get the front brakes to lock up before the rears do unless the pressure is so restricted the front just don't work well.

There is also a kit that allows you to upgrade your front brakes using late model Tacoma rotors and calipers, that will give you a lot more clamping force than the 4Runner upgrade. I will probably go to that setup and use a T100 disk front/drum rear master cylinder. There is bias built in to that MC so it moves less volume to the rear brakes, hopefully that will help the fronts lock before the rears.

As far as residual valves you should run a 2 lb unit on disc brakes and a 8 to 10 lb unit on drum brakes.

ianacole
04-27-2011, 02:13 PM
Randy,

I am not stopping well. There were a number of times on descents at Chinaman Gulch that I felt the need to pull the parking brake and put it in park to feel confident that it wouldn't move.

rover67
04-27-2011, 02:24 PM
There is also a kit that allows you to upgrade your front brakes using late model Tacoma rotors and calipers,

got a link this is interesting...

Air Randy
04-27-2011, 03:11 PM
got a link this is interesting...

Go to the Front Range Off-Road website and click on the link from Brakes. Their kit is $99, you also need to supply Tacoma rotors, calipers and a set of IFS wheel hubs. They also have an upgrade to even larger rotors/calipers and their kit is $129 because of the larger brackets required. You have to ask for it as it isn't shown on their web site yet.

Air Randy
04-27-2011, 03:17 PM
Randy,

I am not stopping well. There were a number of times on descents at Chinaman Gulch that I felt the need to pull the parking brake and put it in park to feel confident that it wouldn't move.

So that isn't right. Even the orignal stock 4 wheel drum brakes will put you through the windshield when they are working correctly.

As I recall you have a V8 and automatic, correct? Keep in mind when in lo range, especially if you have deep gears and you're idling a little too fast, the vehicle will want to "drive through the brakes". That may be part of what you're feeling. How does it stop when driving on the pavement at higher speeds?

Lets make sure what you have is working right before you start spending the bucks un upgrades that may not be required.

ianacole
04-27-2011, 03:23 PM
The stopping on highway is my bigger concern. I give a lot of room to stop as it sometimes feels I won't stop in a reasonable distance. A pad replacement should help with this, but I figured if I can find a better stopping solution at a reasonable price and amount of effort it would be a worthy upgrade.

Air Randy
04-28-2011, 07:09 AM
The stopping on highway is my bigger concern. I give a lot of room to stop as it sometimes feels I won't stop in a reasonable distance. A pad replacement should help with this, but I figured if I can find a better stopping solution at a reasonable price and amount of effort it would be a worthy upgrade.

You can go that route but my advice is to fix what you have first. Once you've done that, if you still want more braking power, then start doing upgrades. As you start doing mods you can run in to problems. If you don't have a good baseline to start from, you won't know if you're still dealing with the original issue or if you've caused a new one with the stuff you've installed. Then you start throwing money at stuff and replacing parts en masse.

ianacole
04-28-2011, 07:41 AM
Good point, and cheaper too. I'll start with the pads. Thanks Randy!

Red_Chili
04-28-2011, 07:44 AM
Changing out brakes on a 40 can be a slippery slope. Going to the mini truck disc setup you already have is an easy conversion and works well. If you decide to go with rear discs there are a lot of bolt on kits out there but then you start to run into proportioning issues. I have the Monte Carlo rear discs and even if I run 2 proportioning valves in series, I cannot get the front brakes to lock up before the rears do unless the pressure is so restricted the front just don't work well.
Strange ... I have my prop valve in series with the rear circuit and if I nearly disable the rears with it, if anything the fronts clamp harder! The truck doesn't stop as well with no rears though.???

Air Randy
04-28-2011, 03:14 PM
I bet it just feels that way. I checked mine with a brake pressure gauge and even when you cut the pressure to one circuit, the pressure does not go up in the other circuit. I also found via my gauge testing, anytime the pressure to a circuit is at or below 600 psi, the brakes on that circuit are virtually useless. On the Toyota MC's I tested the average was 1600 psi at both the front and the rear.

I think the lock up issue I have is mostly due to the MC I am using. I installed the Marlin FJ80 MC that is setup for front and rear disc brakes. I think it is moving too much volume to the rear discs. Because they are huge Monte Carlo disc/rotors, with equal volume/pressure as the fronts, they just over whelm the Toyota units in the front. If I go to a T100 MC that has a different rear bias (moves less fluid to the rears because they were drum brakes) it may be enough in conjunction with the Prop valve to get them better balanced.

Air Randy
04-28-2011, 03:16 PM
Good point, and cheaper too. I'll start with the pads. Thanks Randy!

Could be just pads, make sure your calipers aren't leaking and be sure to bleed them to get out any air. If you have drums in the rear make sure the shoes are good and they are properly adjusted. If that doesn't work then you should check the pressure on your MC.

Red_Chili
04-29-2011, 10:00 AM
Assuming something else isn't wrong as described above, the IFS large capacity calipers with FZJ80 MC and V6 booster will definitely yield more stopping power rolling big meats. Depends on what you need.