Re: 225 70 14 to 205 70 14 Can I ?
What is the stock tire size for your truck? Check the driver's door jamb sticker.
If the stock tire size is 225/70-14, the 205-70-14 will be 4.2% smaller than stock. So your speedo and odometer will be off by this %. A rule of thumb for most newer vehicles is 3% max (ABS, etc)....since most truck off road enthusiasts upsize their truck tires by more than 3%, this is usually not a significant issue.
I have had 205/75-14 on my older Mazda RWD truck (stock is 225/70-14) since stock tires are hard to find. I have noticed that the load rating of these tires changed from 98 (stock) to 95. Since I don't haul much, I was fine with lower load capacity of the smaller tires....I just increased the tire pressure from 35 to 38 psi to help offset the lower load capacity.
2010 Ford Ranger FX4
Armaguard sprayed on box liner
Truxedo Low Pro QT tonneau cover
Studded General Altimax Arctic P245/75-16 winter tires on black steelies