There is no indication that the Pilot has Dolby digital decoding which would approximate a 5.1 system. The 5 refers to 5 speaker channels (center, L front, R front, and L surround, R surround) with the ".1" a low frequency speaker.
If it had 5.1 (or "4.1") then the L rear and R rear speakers would only play the surround sound channels and you would hear nothing but echos and such from these speakers.
Sorry, but the Pilot simply has stereo sound (L and R) with one speaker being a subwoofer. The number of speakers does not indicate surround sound. If it did, then my college car would have been a 12.1 system.
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Hands free device = good
Not buckling your kids = bad
'06
Black EXL-Navi: autodim mirror,
many cargo accessories, mud guards, ODB II, and
wwong's console pads.
'06
Black Volvo XC90 2.5T
'03
Black EXL-RES: side steps, autodim mirror,
many cargo accessories, roof rack, and mud guards.
--> traded in '06 for XC90