Steering box ?

[1-PU70]

1 - What year did the fittings for the hoses to the steering box change to metric?
2 - Can I use any steering box from a 1/2 ton pickup up to the change year for my 70 1/2 ton 2WD with PS?

[cranknut67]

I am not sure of what year it was they went to metric, but I swapped a 67 to a 77 front end and used the 77 gearbox - but I wanted to use a 67 impala pump ( keywayed ) so I had to cut and reflare the pressure hose with the metric setup. pretty easy stuff. pretty much the only thing you will have to worry about is making sure the steering goupler to the steering wheel is the same spline. some are bigger. other than that it should bolt up to the frame perfectly.

[bigskiohio]

There are adapters for that conversion but i dont know where. I used 80 pump and box the 70 frame already has dimple in it for box. i notched inner fender a little for newer hoses. here is some pics

[72C203503ONTHETREE]

I prefer the old style fittings, the metric ones use a rubber opring to seal and they tend to leak if they get moved around very much. I put a newer Z28 steering box on my 83 El Camino(had metric stuff allready) for quicker ratio. Worked great but blew out a rubber seal not long after I installed it, and it was all new(rebuilt box from Autozone with new o rings). I even lubed the o rings before I put therm in. The reseal job seems to be holding up , but havent driven the thing for 5 months.