front end rhythmic humming

I have a 2006 DC Tacoma 4.0 V6 6 speed manual with 214k miles. Runs and drives great but after hitting 55mph a rhythmic humming starts occurring under the driver floorboard and I can feel the vibration with my feet. You can feel it on the passenger side but barely.

There’s a 6in lift with 35’s but there’s no wobble in the steering and the alignment is pretty spot on. The transmission, flywheel, and clutch were replaced 20k miles ago and it’s mostly isolated to the driver’s side so I don’t think those are the issues.

The vibration is best described as a triple hum with about a 1 second pause in between starting at 55mph.

Thoughts?

 

Wheel bearing or needle bearing in the front differential.
That’s where I’d start looking.

Does the noise continue if in 4WD?

 

I haven’t tested it higher than 20mph in 4wd and haven’t noticed it.

 

Does the noise change when turning or going around curves?

If the noise is gone or substantially quieter in 4WD, it’s usually the needle bearing.
It’s not as common to occur on drop bracket lifts, but can still happen.
It’s been known to happen on stock trucks (like mine).

 

It gets quieter on turns and goes away while going downhill in a right hand turn.

 

I’d start with inspecting the wheel bearing on the left hand side.

BTW, unless they are really bad, don’t expect any play in them when the wheel is off the ground.
When the wheel isn’t on the ground, there is not a load on the bearing. It won’t make a “noise”.
When mine was bad, you couldn’t “tell” it was bad by spinning it until it was off the truck.
Between the wheel, tire, rotor, and CV, there was just too much keeping you from felling and hearing it.

If you can her a noise with the wheel off the ground and spinning it or shaking it.
It’s REALLY bad, change it as soon as possible.

 

Before digging too deep, be sure your tires arent cupped.

 

Awesome. I’ll keep you posted. Thanks for the help