Your 10 bit ADC value may be left justified in the 16 bit integer (in the most significant bits). To right justify the ADC value, add this statement to your initailization:
Code:
ADCON2bits.ADFM = 1; //Right justify the 10 bits in all ADC
More info on this register is availiable on page 215 of 380 of the PIC 18 datasheet (Lit #39609b) on the Microchip website. Hope it helps you Mike.