vibration???

Hi there, i am new here and need some help. I just bought a 98 classic with 105000 miles on it,. At certian speeds there seems to be a vibration , its a low vibration kinda feels like a big subwoofer putting out bass, i can feel it through my but and it kinda seems like its comming from the back half of the jeep. I mostly notice it during acceleration and at around 55-60 i can feel it along with some steering wheel shimmy.At other speeds though its not there its smooth, I just had all 4 tires rotated and balanced. Any ideas?? Thanks.............

Do you feel it when your just starting out from a dead stop? When its vibrating at the higher speeds and you take your foot off the gas does the vibration seem to weaken? If so i have had the same problem with my wrangler...let me know...

-alex

It sounds like a u-joint that's worn and needs to be replaced.
Try parking your vehicle on level(turn your engine off. . .), place the vehicle in park, put the E-brake on, crawl underneath it and wiggle the driveline. Does it show appreciable play/rotation? Do the caps on the joints show dried grease and shiny metal specks?

If you answer yes to either of these questions, replace them. Ujoints are cheap anyway. $20 for a good Spicer replacement Ujoint with zerk fittings. . . .