So I got a spektrum dx3s and a spektrum Sr 3300T receiver and it binds fine but the failsafe won't work so I want to buy one but I can only find ones rated to 6 volts and I'm using lipo 7.4 volts, any help would be appreciated

Failsafe should work.

Tried everything, I've got a losi eight 3.0 and I had to reduce brake travel down to about 50% cause it was making my radio tray twist,brakes work fine, would this affect the failsafe maybe?

you do realize on spektrums that the fail safe default is set when binding?

Yeah, I apply brakes when binding, binds fine but when I turn my radio off failsafe doesn't work