landing gear

I have been working on a neighbors 5th wheel landing gear. He broke the original plastic gear box and has a new metal one that fits fine. The trouble is, it is nearly impossible to lift the trailer manually. The new gearbox is a 3:1 ratio. I do not know what ratio the original was. Does anyone know if there are different ratios available for these gearboxes? I have searched and it is nearly impossible to find any reference to the gear ratio on these replacements.