Thanks for the commentary folks; guess I'll have to read the manual some more and come up with the relearning procedure if I go ahead with the "5-plan"
Only Limited Editions after 2014 have an ECU slot for a 5th TPMS id.
You could add a sensor to the spare and reload the sensor IDs for the rolling wheels at each rotation. Does your truck have 5 pretty wheels? My trail has a plain steel wheel spare.
Good faith question: Why 5 tire rotation?
I've got the steel spare as well. Reasons for 5 tires in rotation are several.
I prefer to have full capability with a spare in use. Not much of a problem with the 4Runner's full size spare, but worth mentioning because of the donuts they're putting in so many vehicles now.
When it's time for rotation - if you do them one at a time, you only have to change 4 tires instead of 5.
I don't like wasting a tire. Having a perfectly good tire up underneath for 6+ years is a waste especially since that may be the useful life. I'm not so sure I want to be running around on a 7-8 year old tire at 80mph.
True that you can replace with OEM tires and maybe have the spare put on the nice rims, but I think that we mostly all agree that the stock tires aren't the best choice and go with another brand.
For the most part, I've rotated 5 tires on the last several vehicles I've owned. And although a bit more expensive when it's time for tires, the overall cost is the same on a per mile basis. That said, I've likely got 3-4 more years of good time with the current unused spare, so it's not critical to replace that right away.
