rear axle ratio change better towing capacity

I would go with 4.88's. I went from 3.55 to 4.56 in my F350 with a 351 and I wish I had gone with 4.88's instead. Only reason I stopped at 4.56 is my truck has a C6 auto, which doesn't have an overdrive gear. If it had the ZF 5speed or E40D 4speed, both of which have overdrive, I would have gone with 4.88's in a new york minute!

I'm also going to change to my other F350 with 7.3 diesel and E4OD from 4.10 to 4.56, at some time in the future.