Looks like the end of a coil spring and parts of the spring seat. Check the front springs.
You will love the 5100's. One of the best mods you can do for your Titan!No worries. And no, do not live in a salt mine. Just bought this truck about 6 weeks ago. Got a bad feeling I will be replacing a lot more stuff shortly. Guess that is what happens when you buy a vehicle after dark. Still seems like a solid truck though.
Ordered 08 4x4 coils and Bilstein 5100's. So at least that issue will be resolved. Wait and see what needs replacing next I guess.