Too many Bytes Using Ultrasonic Sensors

Question

I need to send one transmission and record multiple distances with 4 receivers, but everytime I use more than 2 receivers, the serial data does not print. What can I do?

P.S. I'm using 5 SRF-02 Sensors, 1 transmitter and 4 receivers all via I2C.

#include <Wire.h>

#define cmdByte 0x00                                 // Command byte
#define rangeByte 0x02                             // Byte for start of ranging data

byte highByte = 0x00;                                // Stores high byte from ranging
byte lowByte = 0x00;                                // Stored low byte from ranging
int range = 0; 
int rangeData;


void setup() {
  Serial.begin(9600);
  Wire.begin();  
}

void loop() {
   D0_1= getRange(0x70, 0x71);  
   Serial.println(D0_1);
   D0_2= getRange(0x70, 0x72);  
   Serial.println(D0_2);
   D0_3= getRange(0x70, 0x73);  
   Serial.println(D0_3);
   D0_4= getRange(0x70, 0x74);  
   Serial.println(D0_4);
}

 int getRange (uint8_t send_address, uint8_t rec_address)
 {
  Wire.beginTransmission(rec_address);
  Wire.write((uint8_t)cmdByte);
  Wire.write((uint8_t)0x56);
  Wire.endTransmission(); 

  Wire.beginTransmission(send_address);             // Start communticating with SRF02
  Wire.write((uint8_t)cmdByte);                         // Send Command Byte
  Wire.write((uint8_t)0x5C);        // Transmit an 8 cycle 40khz burst - no ranging takes place
  Wire.endTransmission();  

  delay(80);                                                           // Wait for ranging to be complete

  Wire.beginTransmission(rec_address);       // start communicating with SRFmodule
  Wire.write((uint8_t)rangeByte);                 // Call the register for start of ranging data
  Wire.endTransmission();

  Wire.requestFrom(rec_address, 2);            // Request 2 bytes from SRF module

  while(Wire.available() < 2);                    // Wait for data to arrive
  highByte = Wire.read();                           // Get high byte
  lowByte = Wire.read();                           // Get low byte

  range = (highByte << 8 ) + lowByte;              // Put them together


 delay(120); 


 return(range);                                                    // Returns Range
 }