Harmonic Vibration after Leveling Kit

I have been chasing this problem for about 3 weeks now. I have a 2018 Tacoma SR-5 full size (4-door) 4x4 short bed. I installed a leveling kit (3" in the front, 2" in the back.). Once the kit was installed, I noticed that I was getting a small vibration when driving (around 25-30 mph) and would continue to increase with speed. The vibration is slight and pulses (about .5 seconds of vibration then it goes away for about 3 seconds).

The first thing I read about was the rear blocks not being tapered. This could cause slight tension on the drive shaft because the lift was raising it to the point of a little stress on the joints. So, I added 3-degree shims to add a slight angle to relieve that pressure. This did not fix the problem.

After the shims, the tires and rims arrived and I had them installed. The rims were the 4Runner TRD black-out rims and the tires were the Falken WildPeaks, both fit without any problems. The vibration still existed after the rims and tires were installed.

The next issue I read about online was the front differential not being aligned which could cause issues with the CV axles being under extra pressure. The solution was to install a front differential drop kit which would help align everything (and potentially take the issue away). Because I didn't have alignment and the front camber needed to be adjusted (because I was experiencing a slight toe in the front), I took it to Toyota to have them install the diff drop and perform an alignment/adjustment of the camber.

Leaving the dealership, the vibration was completely gone and there was no issue.

This morning, I started the truck and the vibration returned. It's slight, but still there.

I am at a loss and don't want to continue chasing this problem, but I am so far down the rabbit hole now, that I would like it fixed/gone.

Has anyone else experienced this issue and, if so, what was the solution?

Thanks, and I appreciate any advice/assistance on this.

Will

 

Search ECGS bushing. Try 4wd, if it goes away, that's your problem.

 

Just put it in 4wd high and it went away.

Well, hopefully, this fixes the problem. Thank you!

 

Good luck.

 

It will.