Originally Posted by tjsmith7700

I have an '03 250 superduty crew cab diesel that I just put new tires on.

285/75/16 is probably the largest you can go. BF Goodrich makes a 295/75/16 but that may rub a little.

I put 2" blocks on top of the springs which gave me room for 315/75/16 BFG allterrains which are about 35" tall, just keep the factory rims or do not go larger than 8"s wide. It should only cost you about $150`- $200` to do that and there are no other things to change just the blocks.

If the '04 has coils I think it is even less expensive.

Hope this helps