Metric and SAE steering hose fitting mystery '79

[stu64]

Just a info post: recently replaced the Hydroboost lines on my '79 C30, found the pressure line wouldn't seat in the steering box. Turns out the box (which is NOT stamped with the metric part number) has the metric seat, but the PS pump and Hydroboost have SAE. The old SAE lines actually seated and sealed in the metric box, i noticed they were really low in the boss. The lines look to be factory, very bizzare. I got the brass adaptors to use the SAE lines but thought this was noteworthy.

Had to reinstall the old line to get it back on the road, it's literally 15-20 thousands longer at the fitting which let the nut clear the boss.

Anyone ever see this?

 

[bucket]

Odd. I've never had my '79 apart so I can't say about that. Do you know if your truck was built very late in the model year? Maybe some '80 boxes made it to the assembly line too soon?

 

[crazy4offroad]

79 is the first year for metric conversion of some fittings & fasteners, such as brake caliper banjo bolts. It doesn't really surprise me you ran into a real mixed bag there. Is it possible the hydroboost & ps pump aren't original?

 

[stu64]

No, everthing is stock. It is odd, I agree. Hard to believe this could make it off the assemblly line but I guess it didn't leak so let it rip. I can imagine the "are we gonna stop production?" conversations.