My original SPC UCAs with sleeved poly bushings on the left; new UCAs with the X-Axis joint on the right.
TL;DR - the last time I got an alignment, the tech mentioned that the rear passenger side bushing on the upper control arm (UCA) was starting to get a bit loose. After some consideration, I decided to install completely new UCAs, with lifetime joints so I never have to worry about those bushings again.
It was more than three years and 120K miles ago that I installed SPC UCAs on the Tacoma. Shortly after installation, SPC came out with an improved design that was a single forged piece of material, with an entirely new type of joint. That joint - which they call the "X-Axis" joint - was essentially a sealed spherical bearing that replaces the polyurethane bushings where the UCA is mounted to the frame.
And so, when I took the truck in for an alignment and the alignment tech (a good one, which can be hard to find) mentioned that my UCA bushings were in need of replacement, I had some thinking to do.
My options - and full thought process - can be found in Replacing my SPC Upper Control Arms ...with SPC UCAs, but the short of the matter is that I ended up getting a great deal from Esteban at SPC and swapped out my existing UCAs for a new set with the X-Axis joint. I'm still a bit apprehensive about the lifetime nature of the X-Axis joint, but only time will tell. If they are a lifetime part, I will be a very happy camper!
Update October 17, 2022 (six weeks after install)
I'm very unhappy with these SPC X-Axis UCAs, and I was misled by SPC about them being a lifetime part. I've added a (long) detailed update to the original story.
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