1999 Volvo XC AWD. There is a vibration begining around 65 mph and continuing on up. Most pronounced at about 70 mph. It feels like when running over the little bumps in the highway designed to let you know you are straying too far off the road, but not as strong. Also no accompanying sound. I have take it to my favorite garage and they diagnosed it as an inner front CV joint. I replaced that as well as left/right control arms (they were worn) and replaced the drive shaft (also needed). The vibration continues and we are all stymied at this point. I also tried switching tires from this car with another Volvo. That did not help, so I have ruled out a bad tire/rim. Any ideas?
Probably something to do with the AWD system itself, not just the driveshaft. Have you had the differential gear oil changed at any point you’ve owned it?
I have not changed the diff gear oil changed - ever. However, the mechanic said AWD problems usually show up as a noise. I will check out the AWD system. Is there a diagnosis process for this?
not really sure. it might be different for different brands
I have something like that going on with my '96 F-250, feels like a U-joint but it doesnt show up till I hit about 65, really bad from 70 up gets worse momentarilly when its vibrating and you suddenly let off the gas.