Correct.

SR5/TRDOR/TRDORP: +15mm
TRD Pro: +4mm

The suspension geometry is the same on all the trims mentioned.

Thanks. That difference, 11mm, is only about a 1/2 inch. Amazing how such a little difference can have big consequences.

I was mystified too that such a small change in offset could necessitate trimming the fender. I copy/pasted this from elsewhere:

When you widen the track of your vehicle with either wheel spacers or changes in offset you increase the scrub radius. The scrub radius is the distance between the center of the tire and the point where the steering axis meets the ground. Increasing the scrub radius contributes to an increased arc prescribed by the wheel as it turns, and it’s the increased arc, primarily, that causes the rubbing.

This is a (mostly accurate) scale drawing of the 4Runner front susension. As the label denotes, it shows a stock 265/70r17 tire on a 7½x17 rim with a +15mm offset. Take note of the scrub radius at the bottom of the drawing:

What if we replace the stock wheel with the very popular 285 tire on the 7x17 rim with the +4mm offset?

Comparing the two drawings, notice in the second drawing that the offset is decreased and the scrub radius has increased.

Looking down from the top, we still see the dashed line prescribing the steering axis. From this view it is apparent that not only is the point of the tire’s rotation on the ground not centered on the tire laterally, it’s not centered front to back either. An effect of this is that as the tire is turned left and right, the leading outboard corner and the trailing outboard corner of the tire prescribe 2 different arcs, drawn in orange.

Now let’s swap out the 265 wheel for the 285.

The arc of the 285 wheel is purple. The arc of the 265 wheel is orange. The 285 wheel fits in the wheel well just fine. So why does it rub? Because the 4Runner is not very tolerant to changes in the diameter of this arc. It’s so intolerant, in fact that just pushing the wheel outboard of the steering axis a scant 4 tenths of an inch, (as occurs when the TRD Pro rims are fitted) causes Toyota to cut the fender at the port. It’s not merely the wheel being pushed outboard that causes the rubbing. It’s the wheel being pushed away from the steering axis that causes the trouble.