i have a question and hopefully i will get a quick answer. my 1993 gmc 2500 extended-cab has a 4.56 gear and i want to change it to a higher gear. see i rarely ever carry or tow anything with this truck, i just like it because 1) it's gm and 2) diesel and most importantly 3) i cant afford a duramax at the moment. while looking for a complete rear axle assembly i wanted to know is there a difference in axle width between a single rear wheel versus a dual rear wheel. i have access to a dual rear wheel axle assembly with 3.something gear ratio. i dont want to have to pick up this rear axle and have to get rid of it if it dont fit.

I'm no expert, but I would think you could just change the ring and pinion. Just remember you need to chande the front too if 4wd.