This is the full version of the song played during the warthog run in the final level of Halo 3. This song has a very pronounced drum track that makes this version of the Halo theme unique, and it is not available on any soundtracks in its entirety.

I noticed the only available versions of this track have the background ambient sounds, which is extremely annoying. This is the original, halo3_trench (played during the "trench run").