this is a bit off topic, but my dads 04 f350 cc lb 5.4 has 3.73 gears, would putting 4.10 gears on it help any? it is'nt used alot, and a couple times during the summer my dad hauls our 32ft camper that weighs roughly 8500-9000 lbs.

 

Does it struggle pulling it up hills or just struggle in general? If so a 4.10 would help a lot but if it's a 4x4 you will have to upgrade both axles so double the price of the job.