Hey there.. 2004 Nissan Xterra ..can't believe i officially had to make a post about this vibration issue in my xterra but I am having a lot of trouble figuring out what is causing the vibrations at the high speeds, then it evens itself out. In fact some times the vibration isn't there if i drive on the highway long enough.. but majority of the time the vibration is there at 65-75. This vibration has been going on for about 3k miles now/2 oil changes, the tires have been balanced, rotated, balanced, balanced at discount tire, bought two new tires put them on the front, balanced again! and vibration is still there.. that was the history of the tires within the last three months/3k miles. All four ball joints were replaced. Then all four U joints on both drive shafts have been replaced, no weights have been thrown off the shafts, && both cv axels have been replaced, the front idle arm has been replaced as well.. all in that order I believe... ...it evened out the vibrations tremendously (they're still kinda there tho) in the steering wheel however I still feel it in my boots or in the bottom of my seat more than the steering wheel now after all this work has ben done... the transfer case && rear diff fluids were changed recently with its recent oil change, which I believe helps smooth things out as well, not the new parts. What should the next step be? Repacking wheel bearings? Another Front end part to replace? Take it to a specialty shop/nissan dealership? Some people have told me to ride it out, but it's too annoying and I don't want to damage my xterra in the long run, it has just about 206,000 miles on it, has been taken across country, while hauling a uhaul storage. Thanks!