Two Arduinos an RC Monster truck and a 4channel long range link

Currently, you are sending binary data over 4 pins.

I think the problem is that you can only send "1"s or "0"s and you are trying to use analogwrite on your TX and analogread on your RX. I think you need to write your code to only use 1 or 0 as for sending and receiving data.

The other choice would be sending serial data over two pins and working out a protocol to parse the information. Such as TX sends "< X2-n, Y1-n, S1-n, S5-n >" to the RX. Rx then will have to separate the information into 4 variables.

  analogWrite(3, X2);      //D3 Transmitter pin
  analogWrite(5, Y1);      //D2 Transmitter pin
  digitalWrite(6, S1);      //D1 Transmitter pin
  digitalWrite(9, S5);      //D0 Transmitter pin
 X2 = analogRead(A5);      //D3 receiver pin
  Y1 = analogRead(A4);      //D2 receiver pin
  S1 = digitalRead(0);      //D1 receiver pin
  S5 = digitalRead(1);      //D0 receiver pin