Replaced 3rd Member, Still hearing Vibrations/ Noises

Hi, I have a 2002 4runner with 117,000 miles. I just replaced the 3rd member after I heard massive grinding noises from the rear end. After swapping in the new third member the heavy grinding noises went away but I am still hearing what sounds like vibrations around 45 mph and increase with speed. I have checked the rear wheel bearings and those feel good. Any ideas?

Thanks,
Charlie

 

My 4Runner, 2001 was vibrating at high speeds and it was a bent rear axle. Did you balance your tires?

 

The tires are balanced so I am pretty confused. Maybe the new third is defective? Also the sound could also be described as a constant scraping noise.

Thanks

 

is it only at high speed? sometimes to help identify noises it helps to drive something solid, like a building or a wall. roll down all the windows while driving beside such a solid object, then roll them up as you continue diagnosis, louder on left or right, more noise through rear open window or front? scraping noises can be difficult, with the car jacked off the ground spin a front wheel while holding the upper arm, feel vibration? If you do you found your noise, be it bearing, or brake splash shield. With the rear off the ground, put the car in gear and rerelease the brake, a long screwdriver can be a stethoscope, more noise from left or right? if to hard to determine use a hammer, or pull park brake cable, stop one wheel, does the noise go away? if not stop the other wheel, rear wheel bearing noise will travel through the whole housing so if you stop one wheel and the noise stops you found the good wheel bearing, if the noise stays the same with either wheel stopped you have a bad pinion or carrier bearing.

 

I followed your instructions and I traced the problem to a bad pinion bearing. I replaced the third member with one from a junk yard and the problem went away. If anyone in the future has the same issue, feel free to contact me.