I just installed the Specktrum 3.0 radio in my truck, everything seemd to be working fine except I don't have full steering. I set the end points to max (125%) but there is still more my servo can do. What am I missing?? Anyone else had this problem or know haw to fix this? I'm still pretty green so go easy on me, I'm hoping it's something basic I'm missing

A servo doesn't move via the radio as far as it it does when you move it by hand. The servo may be able to move more but can the steering move any farther on the truck? Do you have the right servo horn on the servo?
need more info.......

It's the stock servo and horn. The truck is a Rustler XL-5. If I change the servo horn will I get more steering?

If everything is stock and you only changed the radio my guess is that it's something to do with your radio settings, other than epa to 125%. Not sure off hand what though, sorry.

Try turning up the Steering Dual Rate. It starts out at 70%.
Grip button B.
Don't overdo it, don't bind the servo.