99 PreRunner 2.7L 2WD - Alignment Question

Hello all. Im due for an alignment. Does anyone know if only the two front wheels get aligned or do all 4 wheels get aligned? I know some trucks dont have the option of having the rear wheels aligned because they're permanent. Thanks

 

I have an issue with parallel parking. My issue is that when ever I parallel park, I always seems to manage to hit the rear passenger tire onto the curb. I dont hit it too hard but it sometimes scratches up my tire. Does anyone know if doing this will mess up my tires or rims? Or if this will mess up my alignment? I hit the curb about once a week. Im an experienced driver...just difficult to see at night when reversing into a parallel park. Thanks !

 

If i remove the gate off the bed will i get better gas mileage. Some people say yes it does. Some people have told me it can worsen your mileage. What do you guys think? Any experienced with this? thanks