I am looking to upgrade my front Dana 30. I would like to do this once, so would like to go with a Dana 60 over a Dana 44 (like a PR44). Is there any issue with keeping my Dana 44 in the rear until I can afford to replace it, or I break it?

 

what bolt pattern will that 60 have?

If it is 5 on 5.5 you will have different bolt patterns, you would need to run an adapter in the rear.

 

I would not waste my money on a 60 unless it had free spin hubs or drive slugs, so you're looking for at least 5x5.5 bolt pattern, as said before. So you need to factor in the cost of new wheels and spacer/adapters for the rear. Also you would want wider than stock.

Beyond that, you're fine. There are manufactures that can make spacers to fit your needs and changes in width/bolt pattern.