I just peeked under the truck and I have a 3 leaf pack. Now wondering what models came with 4 leaf packs? I'm about to swap mine out for a set of used OME 2.5" lift springs I picked up yesterday.
Yeah, I was just curious what you had.
We actually talked about it in another thread but tl;dr is that all 05+ Tacomas in the U.S. got a 2 main + 1 overload stock.
I put leafs from a 2016, regular cab SR on my trailer when I was building it, figured I could mock it up and change it later. They were soft so I did a cheapo add a leaf. Pretty close but I'd but I need another hundred pounds of load for dealing with the bigger and higher speed hits on the...
risingsun4x4club.org
For a while Toyota offered to uprate your pack if you complained, which got you a 3 main + 1 overload set that Jack is looking for. Those are known as "TSB springs" colloquially. They're actually springs as I understand it you could get on a commercial spec truck in Canada or Mexico.
At this point if you have the standard springs it's easiest just to make your own pack with add-a-leafs or do replacement springs than try to get uprated factory springs. I think the TSB only covered 2005-2011, although 2012+ may just be under a different TSB.
The issue is that there was a subsequent recall for corrosion issues that could lead to a broken spring puncturing your gas tank. The recall springs have more clamps to hold the pack together. This is something you should do, obviously, and if you have 2+1 packs there's no reason not to get those replacement springs. I got a set of those put on right before I picked up my OME packs, just to have them. But I only had regular duty springs so there was no downside to doing that.
However if you already have TSB springs and go in for the recall there's a chance that you won't get 3+1 back. The recall does give the correct part number and direction to replace old 3+1 with new 3+1 with extra clamps but whether the dealer has them or bothers to order (or even still can, they may not be available for all I know) them isn't universal. So you might be better off keeping your old TSB springs and watching them for rust or putting your own extra clamps on.