78-79 bronco steering box

[red hot71]

There's two different size fittings on the box large, small. Largest closest to the steering shaft input. Smallest to front, pinion output side. Which one is pressure in and which one is return to pump?

 

[DirtDonk]

The one furthest forward, towards the box is pressure. The one to the rear, closest to the shaft is return.

 

[DirtDonk]

Among the boxes I have seen, and bothered to look at closely, the port location is a universal truth.
If one is further forward than the other, that is the pressure line.
Outwardly, it just seems like the low pressure is always closer to the shaft seal. That may have nothing to do with it, as the areas may be completely isolated. But in my little pea brain, that popped in and made sense.
Port size, however, does not seem to be Universal. Yes, most of the ones I’ve seen use the smaller fitting for high pressure. But I don’t know how often that is swapped around.

 

[1969miller]

the pressure side is 1/2in 20tpi and the return is the 5/8 18tpi