SO what causes that wheel shimmy/bumpsteer after installing bigger tires?

do you think its the actually steering components?

 

it’s everything. a 33-34”, wide tire exerts a lot of force on the rack and all associates components.

 

Too much positive scrub radius causes bumpsteer. Your tire/wheel combo adds about 1" of scrub radius.

No way to fix it except new wheels or taller tires.

It will affect your ideal alignment.
All that additional scrub radius is going to have you toed out on a factory spec alignment when road force is applied.
This can also affect your rolling camber.
Watch for wear on the inside.
33"s also want about +2.5 on caster

 

I just gave up on my BFGOODRICH ko2’s.... couldn’t get them to balance and one was out of round. I put Duratracs on yesterday and the steering wheel shake is gone and so is the vibration on the seat.. both brands are 265-75r16 E rated. The Duratracs are 2.6lbs lighter for what it’s worth. Hopefully I can keep these tires longer than the 26,000 miles that I got out of my KO2’s.

 

Love my duratracs as well

 

I have heard too many horror stories with BFGs on Toyotas. I have had them on my Suburban's for 20 plus years and they are hard to balance and keep balanced. Its a very high maintenance tire. I chose to stay away from BFGs and went with Toyo Open Country at2s inn 265/70/17 on TRD Pro Sema wheels. No issues.

 

285/75's and they dont rub on stock suspension ?

 

New owner. Have 31 X 10.50 15LT's KO2's on my 4Runner and they don't shimmy and are quiet. Third set. When the time comes it sounds like I need to go the Duratrac route on this Taco though. Educate me about these Duratracs: Are they as quiet as the KO's?

 

I have similar steering issues with my truck. It started around 10k miles and at that time everything was stock. Dealership said it drives fine and based on other issues I came in with, I decided to not argue with those assholes. The wierd thing about my truck is there are some days when it drives okay and some day where it drives like I'm going to blow a 0.16.

I now have 285/75/16's, -12 offset wheels, king suspension with 2" lift, and new tie rod ends. My issues are still present. I have had 4 alignments over the past 35k miles. It always feels good when I get it from the shop and goes to shit after 3 days. The last alignment felt the best but it still didn't last.

The issues I notice while driving are wheels not returning to center, bumpsteer, and drifting left AND right at random times.

I really want to have an off road capable truck but the way this thing drives absolutely sucks. I am going to bring it to a shop within the next couple weeks and have them go through everything they can think of.

 

Some of the wander is the wider tires and the crown of the road. The bump steer, I'd say you need arms and adjustable ball joints to dial in some more caster

 

Both low caster issues. The drift is likely road shape, but the caster is so low the truck is too easily impacted.

 

I have JBA UCA's that are maxed out on caster.

 

It’s the -12 offset on your wheels. If you can swap on a set of stock wheels. I bet that fixes the issue.

 

Had issues before the wheels.

It doesn't sound like everyone with this offset experiences these issues though. I doubt this many people would run offsets for bigger tires if they had to deal with this all the time. I feel like something else is wrong. Possibly the steering rack?

 

Did you change to a taller tire when you had stock wheels?

 

Your work truck weighs a whole lot more then the tacoma does. And you're putting tires on your tacoma that are designed for a vehicle much heavier then the tacoma. Of course it isnt going to drive right

 

Exactly my question. Fitting 285/75 usually needs lift. Then a re-align. I bet caster is off

 

265/70 is factory stock size on OR although they are 16' vs 17. That size shouldn't cause issues unless something else is out of wack.

 

No, stock tires

 

They rub like crazy. It’s getting better. I just hit LA potholes harder and faster and whatever rubs is starting to wear.