All 95 and later Tacomas are C-channel. Not sure if you guys know the diffrence between C-channel or not. A fully boxed frame, as in the pre- 95 trucks, is a rectangular box without a seam. A C-channel frame is a rectangular box, but there is an overlap where the two sides meet, and it got welded there. The whole Tacoma frame is like this upto the rear-end where the frame opens up. These C-channel frames are supposedly not as strong, but they do flex better. I'm not sure if it's beter to have a fullbox frame that is stronger, but don't flex that well, or if it is better to have one that flexes. I wheel my C-channeled Taco moderately hard, and have had no problems.