So I've been struggling with an annoying noise for quite some time. In the past it was more in the background but now it's getting worse and is driving me nuts. I can best describe it as "whomp, whomp, whomp, whomp..." that follows speed of the wheel, not revs on the engine. It's getting to the point that I can feel a subtle vibration in the steering wheel (not like an out of balance tire), and in the gas pedal, and in the floor. Best noticed anywhere between 20-40 mph. Feels very smooth at highway speeds (65+).
I took it down to my nearest Toyota dealership and they swapped wheels/tires with a stock set and it appeared the sound/vibration was gone. I only got to drive it around a couple of blocks though. Not knowing if it was the tires or the rims, I decided to try some centering rings (my rims are lug-centric apparently....Raceline confirmed that on the phone) to see if that solved it. It didn't. Maybe the truck felt a little smoother on slow speeds, but that was it.
The wheels and tires were balanced 3 times in the space of two weeks, one of which was road-force. It didn't make a difference. They said each time that the wheels were out of balance. Two different tire shops took a look at the tires (Goodyear Wrangler Duratrac 285/75-16) and they saw no problems...no feathering, cupping, etc. The shop I bought the tires from didn't seem willing to help out much with a replacement set should that be necessary. The tires are just over a year old, less than 10K on them with tons of tread, rotated on time. Running 35 psi on all four. Truck has been aligned twice and is straight as an arrow on the road. I should mention that it was making this sound on my old set of tires (well-used Nitto Grapplers) and seemed to go away once I put the new Duratrac's on.....for a while.
I want to get the problem resolved, but don't want to keep throwing money at it if I don't know what's causing it.
What do you think? Wheels? Tires? Or am I completely wrong and it's something like driveline, CV axles, or transmission? I'll look into any possibilities.