Nissan Patrol 160 2door.

Since I bought this truck, I've had a few days where my brake was working properly. Many problems were fixed.

But now, it seems that no matter what I do, it can't be fixed. It pulls lightly to the driver side when braking. ( I think the passenger side is weak)

Let me list all the things I've done:

Check and cleaned all the brake disks and drums. No grease or contamination.

Replaced all the brake pads and shoes (that was a while back); double checked for contamination very recently.

ZERO play in suspension; all components are in perfect shape.

Flushed brake fluid.

Lubricated all the caliper pins

Replaced the brake hose for the side that I thought was weak.

Bled all the system multiple times. Pedal feels solid.

Adjusted rear drum brakes perfectly.

Did an alignment.

Balanced my tires.

Tire pressure is good.

Swapped the front tires left and right.

I don't think much left to check. Maybe master cylinder or front proportioning?

Here's some other info:

Brake fluid comes out with pressure from every tire. No leaks in caliper or rear cylinders. Caliper cylinders move back inside smoothly. Brake pads wear evenly. Brake pedals feels smooth and solid. Braking power is good. Rear brakes don't lock up before the fronts do. When lightly braking there's no pull, when braking so hard that the tires lock up, there's no pull also. Only when braking mildly or a bit heavily there's pull.