Rotational vibration under 20 mph

So I've been trying to track down the source of this vibration for about a month now and I could use some help.

Problem:
Rotational vibration under 20 mph. Vibrates during any deceleration whether breaking or not. Still vibrates when 4wd is applied or shifted into neutral. Vibration is mainly felt in the pedals/floor. Also slightly heard but that may just be me. You know when you feel a vibration and your mind tricks you into what you think it should sound like. Maybe that. Anyways here's all the important info.

Back story:
2015 Tacoma TRD Sport DCSB 4x4
OME 3 inch lift with dakars
1/4" drivers side top plate spacer
Brand new cooper discoverer st maxx 255/80/17s
Factory wheels

What I've already done:
Shimmed carrier bearing
3 degrees leaf spring shims
Balanced and rotated tires
Replaced drivers side CV axle and hub/bearing assembly
Greased drive shaft zerks
Torqued all suspension components
Checked u joints
Check ball joints

Thank you for any ideas of what to try!

 

Bent brake caliper bracket or warped rotors?

 

Not bad ideas. Anyway to test these theories before throwing parts at it?

 

Have you checked your drive line angles at transfer case and pinion yoke. You may need to shim your axle.

 

I have. I shimmed from factory setting to approximately 5/8". Throughout all the testing the vibration did not change in anyway. I'm not saying it's not a drive line vibration, but I assume it would've changed in some way by adjusting the shims. I've been wrong before though.

 

Take the wheel off rotate the hub...it should turn with little drag...the drag should feel consistent. Check the brake hardware make sure nothing is binding. Or have a shop inspect it they have the proper measuring tools...they can give an estimate... estimates are free at most places and your under no obligation to buy.

 

I'll give that a try tomorrow and post back with results. Thank you very much.

 

I'm not talking about the carrier bearing shim. You need to measure the angle of the transfer case yoke and diff yoke and match the angles the two yokes should be in a parallel line.https://www.tacomaworld.com/threads/drive-shaft-vibrations-solved-step-by-step.244535/

 

Ah gotcha. Here's my most recent measurements.

 

Does it feel like a torque converter shudder. Have you checked trans fluid level?

 

I have no idea what that would actually feel like. It's definitely a rotational vibration and not constant. I can check that tomorrow when I'm going through the other ideas as well. The transmission is supposed to be at normal operating temp to check fluid level right?

 

115-130°f

 

Sweet, thank you. I'll throw it on the list for tomorrow.

 

Just tested this. No extra resistance or running when rotating either front rotor. Anything else I should check before putting tires back on?

 

Check the ball joints and wheel bearings...place the truck on the ground grab the tire at 10 and 2 o’clock push and pull back and fourth...shouldn’t hear any clicking noises or feel any play. Check the motor mounts and universal joints on both driveshafts

 

I have already checked wheel bearings, ball joints, and u joints. Sorry I forgot that in the OP. Am I just checking torque on motor mounts?

 

By this do you mean it’s a pulsing vibration?

 

Next time you drive when you come to a stop do it in gear (D) then try it in neutral (N) . If it does it both times it's brake related if it only does it in gear(D) it's driveline related.

 

That could be another way of saying it. It feels like the vibration is in sync with something that rotates. I.e. hub, drive shaft, wheel, etc.

 

Set the parking brake put the vehicle in drive give it some gas may have to use the foot brake as well to keep truck from moving....have someone looking at the motor see if it lifts up indicating broken motor mount.
If all is good maybe the needle bearings in the front diff carrier are bad or drive line angles are off