RC 6 Inch lift Vibration with Carrier bearing drop installed

I have a 2018 Tundra Limited 4x4 has 32k miles on it, I've recently had a 6 inch lift installed, I've also had the carrier bearing drop kit installed using all 6 shims 3 on each side. My issues I am having is when driving and I left off the gas after 30-40mph I get an annoying vibration sound last a few seconds, when I press back on the gas I get a small split second vibration sound. I've attached a picture of the spacer on the back, does anyone know if it looks like its going the right direction? Rough Country asked that and I couldn't answer that. Besides that question from rough country they haven't been able to help me. Any other thoughts of what I can do, I'm at my wits end?

 

What you have pictures is a leaf spring. The carrier bearing drop is something different

 

This is an Ekstrom (Coachbuilder) spacer setup

 

This is a carrier bearing drop kit. Probably what you need to get the vibration to go away

 

I have that installed and it still vibrates.

This is what I had installed https://www.roughcountry.com/carrie...lCAiHKF5AWCQ53BVAwB1xZEUPIJLK3LcaAhQmEALw_wcB

 

Correct. I have one.

 

How thick are the spacers?

 

This is what I used https://www.roughcountry.com/carrie...lCAiHKF5AWCQ53BVAwB1xZEUPIJLK3LcaAhQmEALw_wcB

 

Maybe you don't need to use all the shims. Have you tried taking one off from each side and test driving it?

 

I have done that one shim then two shim and then three shim. the third one gives me the less Vibration.

 

Maybe you need one more

 

Wonder what would happen if you added another.....

 

I might have to try, Rough Country hasn't been any help at all.

 

Sure it’s the driveshaft? Maybe a tire is out of balance. Was it aligned properly after lift?

 

Yes, the alignment was professionally done, after the install. new tires were put on and alignment done at that time.

 

I wouldnt put bigger tires on it until you figure it out. That will just make it harder to diagnose. It sounds like the angle of the driveshaft is off slightly causing the vibration. Doesn't their lift kit come with shims? I would use the one they supplied first.

Also the lift blocks are directional, they should be installed so the axle pinion points up towards the transmission with the fatter end of the lift block facing the rear. I cant tell from your pictures if it's correct or not.

 

It doesn't come with shims in the lift kit, you have to buy it separately.

 

Hmm strange they dont include that. Can you take a better picture of the lift blocks from the side?

I might have some shims from my fabtech kit laying around. I didnt need them on my regular cab. I will try to find them and measure them.

 

The shims from my fabtech 6" lift kit measure 1" thick. Their kit uses an angled 3" lift block in the back.

 

Which RC lift did you go with

 

Do these pictures help?

 

I did the 6 inch Lifted Struts with the V2 Monotube shocks

 

Yeah those are better. Still hard to tell though. The lift block in the second picture looks backwards to me, but I dont know if RC uses angled blocks or not. I assume they do.

I would measure them to make sure. The shorter side towards the front and the slightly taller side to the rear.

It kinda makes sense to me if they are backwards. In my experience the slower the speed associated with the vibration, the worse the driveshaft angle is.

 

Good call, I just measured the side closest to the front is taller and the side closest to the rear is like a 1/4 inch shorter.
Thank you kind sir!

I'll report back once I get it fixed.

 

Here's my old angled block.


Here is my CB spacer dropping my carrier bearing. My lift kit didn't come with a drop.

 

You need to figure out your working angles at the rear diff and carrier bearing, then try to make them the same as close as you possibly can. This will also force you to make sure the lead (shorter) drive shaft is also at the same angle as the working angle on the transmission/transfer case U-joint.

Here’s a very good video explaining it:
https://youtu.be/f1m-Fh5kiRU

 

To start with, your shims may not be thick enough. Coachbuilder kits are 3/4 thick for 0-2 inch lifts, and 1.25 for 3-5 inch lifts. If yours are not 1.25 thick on each side, I would ditch those shims and get the Coachbuilders. The 1.25 comes with the longer bolts as well. The taper on the blocks will make a difference for sure, especially since they were installed backwards. On that note, do not reuse those ubolts, especially with that size block. Ubolts are designed for a one time use. And yes, RC's customer service is not the greatest.

 

That was the issue, no more vibration!!! thank you for your help greatly appreciated.

Now time to decide on an exhaust...

 

I need to play with mine some more. Dealership installed a CB drop kit today but still has a shudder. Was hoping it was going to be that easy.