I recently bought a used 2005 F-350 dually diesel. It has a 4:30 rear end. Can I swap out the ring and pinion for a 3:73? If so, how, or should I take it to a shop?

CWJ

 

I believe that the 3.73 is a 10.5" ring gear and the 4.30 is a 11.25" ring gear. Not sure if the housing is the same size as the 10.5" is a DANA 70 and the 11.25" is a DANA 80. You'll also need to check axle spine count. Might be easier and cost effective to just go to a bone yard for a new wreck.