Drum brakes on the front of a 78

[Cornhole]

Any idea why my 78 fj45 has drums on the front. I thought they switched to disc a couple years prior. Just wondering if I have an older front axle swapped in?
I have a front axle from a fj78 prado kicking around and was wondering if anybody had swapped the disc brake set up over from a 70 series before? I know guys swap mini truck knuckles to get disc brakes. I haven’t pulled the axles to check splines yet on the 70 but I’m guessing it’s fine tooth and mine is course. It would be pretty awesome to swap the coil spring front end to the 45 but that’s probably more Work than what it’s worth right now.

 

[whitey45]

Depends on what market it’s from, South America got drums from the factory.

 

[1911]

Depends on what market it’s from, South America got drums from the factory.

This. Most foreign (non-U.S.) markets had drum brakes.

 

[too tall]

Wanted - 3" FJ45 brake drums

I know there is a set out there some place! 43512-60020 they are the vented drum...the ones on the left! Or maybe there's another drum off a different vehicle that I can use? Thanks!

forum.ih8mud.com

 

[Cornhole]

Yeah, my fj45 is Canadian

 

[bikersmurf]

My 77 Fj45 still had drums. As far as I know 45s didn’t get discs.
I believe the knuckles and discs will be a direct swap. The Birfields and axles are the same on my 45 axle. 70 series may be slightly different width, but you should have everything you need for front discs.

You will need an adjustable proportioning valve... otherwise the rear brakes will be locking every time you hit the brakes. It’ll really startle people who step out in front of you (in my experience).

 

[Cornhole]

Proportioning valve is on the shopping list. As is a bigger booster. I doubt I’m using the brakes though from the prado. I’m thinking I will run Lexus gx470 brakes on all 4 corners. It’s the newest vehicle that Toyota made with 4 wheel disc and still on a 6 bolt pattern. I could be wrong but I believe the 100 series swapped to a 5 bolt. The Lexus should have good product support for years to come and I can go into any parts store and get parts off the shelf while maintaining Toyota reliability. I see people get brackets made for Monte Carlo brakes on the rear and I assume it’s for a mechanical e brake. I would rather have the bracket fit Toyota brakes and have the booster and system that’s meant to work together in the truck

 

[navydivedoc]

Proportioning valve is on the shopping list. As is a bigger booster. I doubt I’m using the brakes though from the prado. I’m thinking I will run Lexus gx470 brakes on all 4 corners. It’s the newest vehicle that Toyota made with 4 wheel disc and still on a 6 bolt pattern. I could be wrong but I believe the 100 series swapped to a 5 bolt. The Lexus should have good product support for years to come and I can go into any parts store and get parts off the shelf while maintaining Toyota reliability. I see people get brackets made for Monte Carlo brakes on the rear and I assume it’s for a mechanical e brake. I would rather have the bracket fit Toyota brakes and have the booster and system that’s meant to work together in the truck

If you get that sorted out, and need to do a run for cnc, etc. I'll be the first in line (rear brakes).

 

[peesalot]

FWIW my stock 1970 drum brake MC runs 4 3/4 ton GM calipers just fine no proportioning valve, stops great.

 

[bikersmurf]

FWIW my stock 1970 drum brake MC runs 4 3/4 ton GM calipers just fine no proportioning valve, stops great.

Sometimes it works out that way. I wasn’t factoring in a rear conversion as well.

From experience I know that the massive Fj45 rear drums have a ton more braking than stock Fj40 drums. With my ‘74 Fj40, 4 drum master, the rear wheels locked up when I first converted to ‘77 Landcruiser disc brakes in the front. In 1994 I didn’t know there was an OEM proportioning valve. Once I installed an OEM proportioning valve that problem was solved.

A couple years later when I swapped in an Fj45 FF axle, the OEM valve wasn’t enough to prevent regular rear wheel lockup. To solve it I installed an adjustable brake proportioning valve. I was able to quickly dial it in to where the front rear bias felt right. A local brake shop was happy to lock’em up on their skid pad. Their fancy, computerized printout showed my foot was dead on. It showed the balance was now bang on.

Fast forward till ‘98... when I converted to rear discs using front rotors, discs, and from a 75+ (Blazer / Suburban / 3/4 ton 4x4 / who knows wat other Chev), the valve needed to be adjusted to further reduce rear brake pressure.

Back to the Brake shop, and low and behold, I was told it was bang on again... even with the used brake rotors on all four corners.