Could also be the ball centering kit on your front driveshaft. It is likely this if you are getting a rotational squeak that is speed related from about 10-50 km/hr. After that the road noises take over. If you suspect this too be your problem, try taking off the diff end of the driveshaft and tie it up really good and go for a drive and see if this fixes your problem. DO NOT PUT IT IN 4WD WITH THE DRIVESHAFT OFF.
HTH,
Jeff