Camber and Caster Adjustments for lifted 2021 TRD Off Road

I have a '21 TRD Off Road 4x4 that I just had a 4" lift installed. I am getting new tires (285 70/R17) and wheels installed next week. The mechanic at Firestone asked me what I wanted the casters and camber set at. As a newbie to this world, I had no idea (I figured that would be something they would know). Does anyone have any recommendations on these settings? Thanks in advance!

 

0 camber 3 - 4 caster 0 toe

 

Thanks!

 

You need arms for 3-4 caster and 0 camber. They are ideal numbers though.

You want highest caster, and lowest camber. Typically you'll get 1.5-2 degrees caster and 0.5-1.0 degrees positive camber on a lifted truck without aftermarket arms.

Tacoma is 0.16 total toe or 0.8 toe each. Not Zero.

 

It depends on a lot of things.

On a stock truck, caster is +2, camber is +0.5 and toe is +0.05. Caster varies +/- 0.2 across the different models, but camber and toe are pretty much the same. There are legit reasons for said measurements; stability, wheel returnability, wheel maneuverability, dynamic accountability, etc.

Most people don't realize, an alignment is a static measurement. Things change when dynamic forces are introduced under acceleration, cruise and braking. When you change the SAI and scrub radius with lift, taller tires and offset wheels, you significantly change the dynamic forces and their interaction with the steering. Not to mention, the changes in steering geometry associated with lifting...

Most often, people will recommend higher caster for no other reasons than stability, wheel returnability and most notably, tire clearance. The latter, I do not consider a legit reason on it's own; not to say there aren't legit reasons for increasing caster. For example, a lifted truck will lose SAI. SAI is +12 on a stock truck. SAI is a stability angle, as much if not more so, than caster. It is the reason you can get by with relatively low caster(+2) on a stock truck. By increasing caster, you are basically you're trying to regain mechanical advantage and stability over the tire by increasing leading trail. But, there are 'costs'...

In general, the more you change things, the more compromises you will need to make.

What is the intended use? Daily driver? Dedicated offroader? Is tire wear critical? Do you want it to favor straight line, higher speed turning, low speed maneuverability, etc.? How much did SAI and scrub change?

So yeah...what do want?
Frankly, I'm surprised a Firestone tech gave you the choice. But, toe should also have been an option.

What kind of lift? At 4", I suspect you have a drop bracket lift? Those usually claim to retain factory geometry; not that I've ever heard anyone verifying it.
What are the specs on your new wheels?