1969 FJ40 Brake Questions

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2nd Phase Front Disc

Dual circuit master cylinder swap complete! I am looking to swap in an fj55 front disc axle and have a few questions:

-Do I need to mess with the new MC?
-Can I eliminate the hard lines from the new fj55 axle?
-Can I use the stock soft lines from my 69 fj40 axle?
-Can I swap the locking hubs from my existing fj40 axle to the fj55 axle
-Can I swap the diff (3rd member) from the existing fj40 axle to the fj55 axle

See reference pics of the new fj55 disc axle. Trying to keep this simple and straight forward swap. Any help here is much appreciated. Thanks in advance.
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Dual circuit master cylinder swap complete! I am looking to swap in an fj55 front disc axle and have a few questions:

-Do I need to mess with the new MC?
-Can I eliminate the hard lines from the new fj55 axle?
-Can I use the stock soft lines from my 69 fj40 axle?
-Can I swap the locking hubs from my existing fj40 axle to the fj55 axle
-Can I swap the diff (3rd member) from the existing fj40 axle to the fj55 axle

See reference pics of the new fj55 disc axle. Trying to keep this simple and straight forward swap. Any help here is much appreciated. Thanks in advance.

1. If your new MC is set up for disks, it should work. IIRC, even the dual mc with drums did fine with disks

2. I would keep the hard lines

3. All I would do is swap axles and replace the cut soft line to tie into your existing system. You may need to create an adapter to bridge from 10mm to 9mm lines. You can't directly swap in the older lines to newer lines. If you got newer 10mm ends, you'll be okay. I think the axle width of the '55 is the same as a 40. It would save pulling pieces. You may have to get another driveshaft flange to work with the newer axle.

The locking hubs from a drum brake axle won't fit the newer Birfs. Also, the you need to bend the hub tabs in pic 1.

If I'm being obtuse, please let me know. Good luck, ty. :beer:
 
1. If your new MC is set up for disks, it should work. IIRC, even the dual mc with drums did fine with disks

no - it really depends on whether the master cylinder is supposed to be for a drum brake model or disk brake model - you can make an original drum brake master work with disks, but you would need to remove the residual valves from those circuits that have disks instead of drums now

if the MC was for a disk brake all around model truck, it should work with disks brakes all around - might need a proportioning valve in the rear circuit if the front and rear disk brakes are not matched

the locking hubs won't work, at least not those from stock '69 axles
 
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1. If your new MC is set up for disks, it should work. IIRC, even the dual mc with drums did fine with disks

2. I would keep the hard lines

3. All I would do is swap axles and replace the cut soft line to tie into your existing system. You may need to create an adapter to bridge from 10mm to 9mm lines. You can't directly swap in the older lines to newer lines. If you got newer 10mm ends, you'll be okay. I think the axle width of the '55 is the same as a 40. It would save pulling pieces. You may have to get another driveshaft flange to work with the newer axle.

The locking hubs from a drum brake axle won't fit the newer Birfs. Also, the you need to bend the hub tabs in pic 1.

If I'm being obtuse, please let me know. Good luck, ty. :beer:

I got the MC from Mark at Marks Offroad and believe it should be fine. Figured I'd double check.

I have no hard lines on the the current axle housing, the lines split in the engine bay. So I am not sure how that would work. I was thinking I could connect the the soft lines to the opening pictured.

The 3rd member on the fj55 axle after 3 1/2 revolutions is stuck. It would not move..so I was hoping I could swap the 3rd member from the current axle. Is that a possibility. That should also solve the drive flange issue..correct?

Thanks for the input..

Cheers
 
I would look at the fj55 diff and see what's going on with it. If it's a simple fix, it'd be easier to repair it than trying to swap the diff out. I'm not sure if they are compatible. I don't think so as the gearing will be different. You can do a search in this forum to check. If it is going to be a PITA to fix the fj55 diff, you can do a swap of all the pieces as you would in a mini truck. That way you would keep you old housing and diff, but you'd have to grind the old axle housing to fit the newer birfs and also exchange the new birf to the inner axle to replace the old coarse spline birf. You should check to see if it is indeed the diff that is the problem.

If you get to use the fj55 axle, you can run a run a hard line from the front line of the brake master down to the frame and then over to the axle. Usually at the junction of the frame and body, there are a couple of turns to the brake line so it doesn't get stressed if the frame and body somehow move apart. The front axle to frame can be a soft line but once again, you can run a looped hard line down but you would have to account for the movement of the axle relative to the frame. You can attach your new soft line/hard line to the t junction where you have the old soft line cut.

When I did the minitruck swap on my '70, I did what i outlined above but used a long soft line to run from the frame to the axle. I created new hardlines to both sides from the t junction and put tombstones in at the caliper junction and ran short softlines to the hardlines that ran to the calipers. I also replaced all the lines with newer and put on 10mm all around except for the lines that go directly to the rear pistons where they use 9mm. I figured if I go to rear disks, I can swap out those lines and have 10mm fittings all around.

HTH, Best regards, ty
:beer:
 
If you get to use the fj55 axle, you can run a run a hard line from the front line of the brake master down to the frame and then over to the axle. Usually at the junction of the frame and body, there are a couple of turns to the brake line so it doesn't get stressed if the frame and body somehow move apart. The front axle to frame can be a soft line but once again, you can run a looped hard line down but you would have to account for the movement of the axle relative to the frame. You can attach your new soft line/hard line to the t junction where you have the old soft line cut.

:beer:

Why wouldn't I be able to just eliminate the hard line on the fj55 axle and just connect soft lines on the 2 sides. This is my current setup on the stock fj40 axle and works fine. I really don't want to mess with hard lines..it is a PITA. I would need to get the correct soft lines with the right fittings. Anyone sell something that would work?

Cheers
 
IIRC, you want to use soft lines when you have to account for movement of the brake lines, such as at the frame/axle or frame/body junctions. The hard lines will last longer, and more importantly, will not expand (bulge) in diameter like the soft lines when they get old and soft. The hard line also transmit more of the pressure to the calipers and drums so you will have better brake response. You can make home made mounting brackets for hard lines or pull them off any toyota or any other vehicle that uses 10mm lines--pretty much anyone on the market. You can also reuse some of the brake lines from newer vehicles if you don't want to pay for new. Here is a source for 9mm male brake nuts:

http://www.brakequip.com/tubenuts.html

If you really wanna go with soft lines, any of the toyota soft lines for 10mm will work. I had collected napa part numbers and brake line lengths and can post if needed.

Hope it goes well, ty
:beer:
 
IIRC, you want to use soft lines when you have to account for movement of the brake lines, such as at the frame/axle or frame/body junctions. The hard lines will last longer, and more importantly, will not expand (bulge) in diameter like the soft lines when they get old and soft. The hard line also transmit more of the pressure to the calipers and drums so you will have better brake response. You can make home made mounting brackets for hard lines or pull them off any toyota or any other vehicle that uses 10mm lines--pretty much anyone on the market. You can also reuse some of the brake lines from newer vehicles if you don't want to pay for new. Here is a source for 9mm male brake nuts:

http://www.brakequip.com/tubenuts.html

If you really wanna go with soft lines, any of the toyota soft lines for 10mm will work. I had collected napa part numbers and brake line lengths and can post if needed.

Hope it goes well, ty
:beer:

Tyama really appreciate the input and info, I am learning and discovering through this process. So I took a few pics of my current axle to brake setup. It is a soft line from the frame junction to the drum backing plate/cylinders, see pic 1 & 2. There are no hard lines on the front axle itself.

With the fj55 axle I would use the same setup and run a soft line from the frame to the backing plate and there is a hard line to the caliper, see pic 3. This should work as it does with my current setup? I do not need to use the hard line on the axle. If I am missing something or not getting what you are saying I apologize. Please set me straight. I am trying to minimize the brake work with this setup. Also would the stock soft line I have now work with the fj55 axle?

Cheers
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So basically unscrew the soft lines from the drum brake axle then screw them into the port (you called out with the red arrow above) on the disk brake axle?

Also it wasn't clear if the diffs were interchangeable? Does the 55 front axle have the same ratio as the 69' FJ40?

The 55 front axle has the hard lines on it along the top of the axle, like the 60/62.. series do. Those are the lines that he wants to eliminate if the oem drum brake soft lines are compatible with the disk brake front axle.
 
Hiya, what you got may not be the oem setup, but if it works and you want to replicate it, you should do it. I just like using hard lines when possible. You can take one of the lines off your old axle and see if it bolts up to your fj55 axle.

Good luck, ty
:beer:
 
I recently finished the lower half resto on my 67 FJ40 with disc brakes all around. The issue I am having is what master cylinder do I go with and do I go with a booster. the rig has a fresh (72 F engine, 3 speed) with the 32 - 36 weber with factory air cleaner. All of the plumbing has also been replaced. I was looking at the Man-A-Fre dual without the booster and also one of these, I am not sure about fitment.. Any advise would be greatly appreciated..

th
 
Is that master from BTB? I'm interested in that as well for my build to keep all the parts easily replaceable, but I have drums in the rear. Looks to come with a proportioning valve, so it might be good with any set up.


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I recently finished the lower half resto on my 67 FJ40 with disc brakes all around. The issue I am having is what master cylinder do I go with and do I go with a booster. the rig has a fresh (72 F engine, 3 speed) with the 32 - 36 weber with factory air cleaner. All of the plumbing has also been replaced. I was looking at the Man-A-Fre dual without the booster and also one of these, I am not sure about fitment.. Any advise would be greatly appreciated..

th

fitment is a problem if you have the fin on the firewall
 
Per DSRTRDR, you will encounter fitment issues if you have the firewall rib. You will need to utilize a spacer or modify the firewall. Also if you are running the factory air cleaner it may interfere as well. I haven't completed my upgrade yet, but I am not planning on running a booster and I am using a Toyota dual MC from a later fj40 with a proportioning valve.
 
we used a 4-Runner booster (from the junkyard) on my 40 when my booster failed recently - it fits the '72 master cylinder and clears the 1F aircleaner that is mated to a 1F carb and 2F motor; a little bit of massaging was required on the small firewall rib in the '72, because the 4-Runner booster has a slightly greater diameter
 
Would you please post a pic if possible?

we used a 4-Runner booster (from the junkyard) on my 40 when my booster failed recently - it fits the '72 master cylinder and clears the 1F aircleaner that is mated to a 1F carb and 2F motor; a little bit of massaging was required on the small firewall rib in the '72, because the 4-Runner booster has a slightly greater diameter
 
67 Pickup, with 2f, 1 barrel and 3 on the tree, disc brake front end


edit, I found an old post which says what I used
booster is from a 74 fj40, master is off a V6 mini truck, adapter for booster(3 bolt to 4 and clears the rib) is from Wardens.


also added an adjustable proportioning valve for the rear drums, not sure if it was needed.

used the existing hardlines that run under the radiator, then soft lines from the frame to the caliper. Not sure what we did with the 9mm to 10mm

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All years have the rib in the same location? Or just the early one that didn't have the booster stock?


...via IH8MUD app
 

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