Hey all, just had my axle ratios changed to 4.10's. I've got a lot of vibration coming from the truck's rear end starting at about 45-50 MPH. The mechanic claims its normal because the driveshaft is spinning faster and because of the extra angle from the lift (2.5" lift whoo-hoo). I'm thinking the u-joint's not been put back right. Anyone else had this problem?