What could it be? Well, based on the shock mounts, it looks like it will retain a solid rear axle, which makes sense considering full-size truck buyers might frown on independent rear suspension. We think Toyota may be working on a coil-sprung rear suspension similar to what the Ram 1500 uses. Air springs could be another possibility. This is speculation, but our theory is supported by what looks like a locating link in one of the images, which would be necessary with coil springs or air springs as neither provide natural fore and aft positioning the way leaf packs do.
Besides the mysterious rear suspension, we can make out just a bit of the front fascia. It's not especially different from the current model, with headlights sticking out wing-like from the big center grille. The grille design looks similar to the Tacoma TRD Pro grille, with room for the word "Toyota" spelled out, and a big center plastic bar. The two-post trailer mirrors are another feature we haven't seen before on Tundras.
This is the first time we've seen one of these Tundra prototypes, so it could be a while before its secrets are revealed. We wouldn't expect to see it for at least a year. We'll be keeping a close eye on wrapped Tundras in the meantime.