Would it be okay to run 3.50 gears in the front and 3.55 in the rear it is that too far a separation?

 

D30s never came with 3.50:1. 3.54:1 or 3.55:1 was the ratio between 3.07:1 and 3.73:1, and are close enough that it's really a matter of semantics. You shouldn't be operating 4WD on anything other than a loose surface anyway.

 

The front axle is a hp44 from a 73 f100

 

Yes fords did come with 3.50 gears to match with the 9" ford rear that came 3.50. Yes you can use a 3.54/3.50 combo with no harm done. The ratios are close enough. This was the only option if the fords broke their front gears since the 3.50 dana 44 gears were discontinued.

Miles