I can't take the shake!!!

February 2021, I buy a set of 275/70/17 general grabbers.

Come August they're cupped bad due to knocking my alignment out after some nasty potholes. I rotate the cupped tires to the rear. I see no signs of evening.
I change from 3" spacer lift to RC 3" strut and get an alignment. I left my 2" blocks in the back.
I said forget it and buy a new set of wilpeaks.
I leave discount tire that day and have a shake at 55-70. Go back the next day and tell them about it. They re-balance them. Leave and as soon as I hit 55mph I feel the shake again.
I get another alignment!
2 weeks go buy I need rear brakes because it was time. So today while I'm at Toyota I tell them about the shake. They said they'd balance the tires. I also asked if the tech could drive after and see if the shake was eliminated. He never does. I also mentioned to them that after a lift the driveshaft can go out of balance and to please check it.
The tech takes 5 hours comes back and says the driveshaft is "fine. Truck is too new for that to happen." He then says that the road force balance states my tires are at 37/31/26/24 readings. Once I leave the shake is there still.
So I call discount tire after since I've dealt with them countless times about the grabbers and the two balances on the wildpeaks in the last 2 weeks.
The guy at discount tire says to bring them back and they'll "look" at them.
Toyota says their tire balance specs are under 20 for a proper balance and discount tire says theirs are 35.

I AM AT WITS END HERE.
What do I do? Do the tires seem to be the problem?
It is a rear end shake. It's a 2017 trd sport dcsb rwd. I'm running vision offroad nemesis 17s -12mm offset. The truck had no problems until the cupping. I have a feeling this is deeper than "some tires just don't balance out/right". Since August I've spent over $2k trying to fix this shake with brakes, new tires, balancing. I'm so lost.

 

It can get rough at times


… all alone

 

Nothing a lil jack can't solve.

 

^ X2

 

First discount tire doesn't know shit and cant balance anything heavier than a civic tire. They'll just throw another 30 weights on and call it good. Cut your losses and move on.

If toyota says they aren't balanced..... I'd start there.

Isit a constant shake or at certain speeds? Only when accelerating? Have you done the ECGS bearing?

 

Hammer hangers will plant that ass end

 

I'm at a lost with:

"....after a lift the driveshaft can go out of balance....".

How?

 

It was 55-70 now its 45ish to 70 after toyota balanced them. I have not done the ECGS bearing.

 

Is the hub bore the wheels bigger than the hub on the truck? I only ask because thats the shake that every single car I have owned has had if I put aftermarket wheels on without hubcentric rings. Most of the time I never got the rings because I never drove 55mph.

 

Plenty of research. You change the angle of the drive shaft with the lift. It can cause vibrations.

 

Must be your area Discount. My Discount balances my 33" KM3s just fine. Tires run smooth and true all the way up to 75mph. I don't drive any faster than that. No need to.

 

Even if it never had the shake for 2 and a half years with other tires and same after market wheels?

 

Did you do a carrier bearing drop or measure your driveshaft angles? There is a tread on it, I’ll take a look and edit this to post it. That might be worth looking into.

Here is the thread I was thinking of. Though since it sounds like new vibrations it might not be it..
https://www.tacomaworld.com/threads/drive-shaft-vibrations-solved-step-by-step.244535/

 

Hmm probably not then. Scrap my idea. Good luck with your search.

 

I put the Icon RTX spring pack on my '17 lifting it 3". Has settled at 2.5" over 20k miles. No vibrations whatsoever. Maybe shitty block lift is causing your vibes?

 

This shake is not caused by the shaft going out of balance. It is from the angles of the universal joints not canceling out each other. This is why spacers are occasionally used to lower the steady earing changing the front and centre u-joint angles.

 

Drive faster and turn up the radio?

it’s probably the blocks btw

 

Get your hands on some stock wheels/tires
from someone and see how it plays out. If you still have issues with stock/stock then this eliminated the wheels/tires. I’d lean towards lug centric wheels. I switched to hub centric and haven’t had any issues since. Good luck

 

I also thought maybe riding the cupped tires in the rear for so long may have done something with the blocks. I just don't know where to take it since toyota here doesn't really deal with lifted tacomas and I think there may be one off-road shop but they deal more with the 20x12/22x12 squatted Chevy trucks. I doubt I'll find help there.

 

I do have my stocks sitting in my shed with the 265s the truck came with. I may have to go this route.