Master cylinder differences (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

The differences to look out for are:

1. bore size, land cruisers used 1" with rear disk brakes.
2. the line pressure valves are different on drum vs. rear disks and will need to be swaped if using a disk brake cylinder on drum brakes and vise versa.
3. front brake lines leave the mc either at the side or top.
4. newer mc's bolt to the booster using 2 blots/studs, older ones have 4 bolts/studs.

In your case, there should be no significant difference since the 'cruiser had a simi float with drums, but maybe where the front lines mount to the mc.
 
All of them should have a 1" bore. If the cruiser has rear disc then the MC will also have a check valve that keeps 2psi (about) in the rear line. Don't use a MC from a cruiser with rear discs on a truck with drums.
 
All of them should have a 1" bore. If the cruiser has rear disc then the MC will also have a check valve that keeps 2psi (about) in the rear line. Don't use a MC from a cruiser with rear discs on a truck with drums.

The check valve for disk brakes does keep less pressure in the lines than what drum cylinders need. You can simply unscrew the valve and replace them with ones for a drum if you use a MC that came with rear disk brakes. You should also do this if swaping to rear disks and the orignial drum MC is not upgraded.

Recent Land Cruisers have a 1" bore, older land cruisers had 7/8" bore.

Trucks/4Runners/Tundras(unsure of '07) all have 13/16" bore.
 
Last edited:
All of them should have a 1" bore. If the cruiser has rear disc then the MC will also have a check valve that keeps 2psi (about) in the rear line. Don't use a MC from a cruiser with rear discs on a truck with drums.


oh great...
 
The check valve for disk brakes does keep less pressure in the lines than what drum cylinders need. You can simply unscrew the valve and replace them with ones for a drum if you use a MC that came with rear disk brakes.


I can't take pics, and don't know anything about brakes...

You got a link? Or can show me what to do?


I've got an IFS rear, one IFS caliper/Fj60 rotor up front, and an FzJ80 master. I haven't changed the other caliper yet.
 
Do you mean just replace the little bolt that come out of the LC master, with one out of a rear drum master?
 
Really? THEN MAYBE YOU SHOULDN'T BE WORKING ON THEM. :rolleyes:


Ok, I'll change my rear end back to the pre-IFS, and remove my vented rotor and caliper, and FJ80 master cylinder.

Thanks for the help!


Amazing how much info there is in this section about that ONE master cylinder...
 
Making a FzJ80 master cylinder work

Well... I knew that was too easy. I got the only M/C that wouldn't work, cheap and delivered! :lol:

Of course not... If there's a pile of sh.. two miles around, I can step in it!




Evidently, drum brakes require a 10lb residual valve in the back, and rear disc's, 2lb...


You can buy in-line valves but my question is, would the 2lb that's already in(?) the FzJ add to the 10lb one I can get?

555-631031.jpg


Or since it's an in-line system, and like a check valve, will it not even phase the 2lb that's in(?) the FzJ80's master cylinder?


The master I have does not have external residual valves...
 
Last edited:
You're overthinking this stuff, it's not that hard.

I have a booster & MC from a '94 V6 truck, my front calipers are the V6 mini-truck ones, and I have the Monte-Carlo RDB setup. No extra residual valve, but I still do have the LSPV installed. It works great, I can lock up 35's.

Bolt it together, see how it works, go from there.
 
Well, I don't have any money, and any brakes...

No, nada, zero, zilch. Pedal to the floor, no brakes!

I've run 2 big bottles of fluid through the thing, and bled the LSPV, nothing!

I do however have a nice AISIN FzJ80 master cylinder... I can't afford, nore want to buy a remanned POS.

I have two 13/16ths M/C's in the shop but don't want to take them off b/c I'd prolly just change the boosters too, and that'll all have to be put back on when I put the trucks back on the road...

And my Fj80 is 100 miles away:bang:
 
Last edited:
Also note: DO NOT run an ABS master on an non-abs truck. Those masters have a much higher return flow rate, which can blow out the seals on a wheel cyl or caliper.
 
Yep, that's me!:bang:

I went through all my master cylinders today and they're all leaking...

damn...


Anybody want a FzJ80 master cylinder? It's got a 1" bore!:rolleyes:


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."
 
Last edited:
Also note: DO NOT run an ABS master on an non-abs truck. Those masters have a much higher return flow rate, which can blow out the seals on a wheel cyl or caliper.

Silly question, GRM... But do you suppose I could rebuild the ABS LC master I have now, with another 1" master that wasn't ABS? Say a 91-92?

Then use a residual valve?


EDIT and for future ref...

Looks like the RTE 13/16ths master is different...

Called the dealer only to get a rebuild kit price of $65.

Napa has a listing. P# UP 1758. Store Locator | NAPA Online

Guy at Napa said it was made by "United American" and on a totally separat parts box, United American was made in China...

$43.99

355830.jpg



Could order it from Raybestos :rolleyes: Part Number: MK1758

Part number look familiar?
 
Last edited:
Can somebody help me?

I just a got re-man from Napa, 4Runner and 91-92 FJ80 are showing the same part #'s.

It does not have the big screw-in residual valves Bear was talking about in his previous post.

My question is, should I just bolt it on and bleed the brakes?

Are the residual valves internal?

Or should a 4Runner/FJ80 master freaking cylinder have residual valves, that screws into the side of the master??

Do those vehicles have in line residual valves positioned somewhere else on the vehicle?

WTH is going on here...

If I bolt this thing on, I'm more than likely gonna void the return, right?
 
Last edited:
Swear to GOD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Napa is saying the P #'s are the same from a Landcruiser 91- 1/95.... So that would tell me the masters have no residual valves in them and they're somewhere in-line...

B/c there is no way the same master will work on drums and discs...
 

Users who are viewing this thread

Back
Top Bottom