Delco 600127 Steering Box, No Synthetic PS Fluid?

[badazz81z28]

Does anyone have a clue why the Delco 600 series box part # 600127 instructions would state NOT to use synthetic PS fluid?? I have Royal Purple in my system now, I would hate to dump it for cheap conventional.

Thanks,

[Ron Sutton]

Hmmmm. No idea.

We run the 600 series boxes & all we run is synthetic PS fluid, with no problems.