In one thread I read spacers could make rubbing worse. I know very little so bare with me.
In terms of trimming, will that effect resale value? Is it something that a dealer or installer will do? How hard is it for someone with 0 experience working on cars, like myself, to do?
Just to give some clarity on this - there are two different items commonly called "spacers".
One is a spacer that sits on top of your front coilover (the spring/shock unit). The purpose of this spacer is to increase your static ride height - the height the truck sits when at rest.
This is an example of a coil spring that has two spacers - one inside the coil assembly and one outside the assembly. Both styles will give you a "lift" in the front.
The other type of spacer is a wheel spacer that bolts on between your hub and your wheel. This moves the wheel outward to give a wider stance. On many vehicles wheel spacers can move the wheel outward in such a way that the tires do not rub. On our vehicles - because of the geometry - the wheel spacers will make your interference worse, not better.
They look like this:
The lift spacer does not help with tire rub because the suspension geometry does not change. The location of the tire is dictated by the a-arms and spindle. If you do not change those, the tire will cycle through the same motion no matter what static or starting point you are set at.
One very common concern with the OEM suspension is that the caster angle is pretty low. Meaning that the front tires have relatively little desire to track straight and the 4runner (and all toyota IFS 4x4s) tend to wander or need constant correction when driving. Part of the problem with this is that in AWD models you would not want as much caster if the front tires are being powered, so it's a bit of a compromise. In order to add more caster you can do one of two things. The first is to adjust the lower a-arm to move the bottom pivot point of the spindle
FORWARD. The result is more caster and better driving dynamics, but it also moves the center of the spindle FORWARD toward the front fender liner and tends to cause a rub there. The other preferred alternative is to move the top pivot rearward. The upper arm is not adjustable - so to do that you need to buy new upper control arms or "UCA"s. Those are not cheap. The benefit is that you can add caster where it is less prone to rubbing.
EDIT: WHAT I HAD ORIGINALLY WRITTEN ABOVE WAS EXACTLY WRONG. To increase caster the LCA needs to move the lower pivot point forward adding more rub in the front. :frusty:
The other consideration is that all of them are different. So where one vehicle may have a slight rub, another will not.
The final comment is that the rub is at the outer corner of the tire. So some tires that have more rounded outer tread will fit without rubbing where another tire with the same "size" will rub. A BFG All Terrain has a very square tread corner that may be more likely to rub than something like a Michelin M/S2. That extra area of ground pressure could be important to some and not to others. A 275/70/17 tire is a nice compromise. Another possibility would be a 265/70/18 with new wheels to have a narrower tire that's just a bit taller. Or of course stick with stock tire size.
In my opinion the difference between a 265 and 285 is more for visual benefit than any significant increase in offroad performance. There's a benefit, but I don't think it'll be a lot. The stock 4runner will be pretty capable as it is with some better stock size tires.
