Info:
80K miles
Diff fluid changed to Amsoil at 72K miles
Recent mods: Rear Bilstein’s, auxiliary body mounts welded on.
No leaks.

I tested the “hum” by coasting on the freeway. Yes, I can hear it in and out of gear - its coming from the rear. It happens in gear usually around 2500 – 3500 RPM.

Kind of a bummer because we are heading out Wednesday night on camping trip to the North Rim of the GC.

My thoughts: Wheel bearing going out, new sounds being heard now that the auxiliary body mounts are finally welded on, rear diff, drive shaft…

Your thoughts/ideas?

 

My guess is a wheel bearing.
Jack up the front end and see if you have any play.

 

If you noticed the hum after your recent mods, I would choose the aux. body mounts (whatever they are) as a likely candidate. Perhaps you're picking up some added resonance.

Otherwise, I would suggest teaching your rig the words...

 

Hopefully it's not the amplified resonance of a wheel bearing that has been bad!

Rick- The aux body mounts come with the RB Body Lift. For some reason Toyota did not put the same amount of mounts that the 97+ have.

Regardless, I guess it is a good excuse to use my new Hi-lift and check the wheel bearings on each side. I hope I am ok for a long trip.

 

My bet would be a bearing as well. The only other thought is maybe you have a brake shoe partially hung up. Slightly press on the brake pedal while rolling down the driveway and see if the noise continues. Or cycle the E-brake a time or two and see if the noise goes away.

 

I have a whistle when I accelerate, but it doesn't bother me, should it?

 

Threadjacker!

 

only if it's whistling TAPS!!!