f5moab - Do you mean the alternator?
If you have a 2WD option, then this is what you should use in typical dry conditions.
Most vehicles with 4WD will have either a 2WD mode as the standard mode for dry pavement, or a 4WD-auto (may be called AWD), as the standard mode. It would be very strange for you to have both a 2WD and a 4WD-Auto mode. Are you sure that your 4WD is not a part-time mode, for slippery conditions only? Your owner's manual should contain very specific instructions on when it's OK/NOK to use each mode.
thebrakeman ('70), DW ('71), DD ('99), DD ('01), DD ('05)
2004 Surveyor SV261T (UltraLite Bunkhouse Hybrid)
2006 Mercury Mountaineer V8 AWD Premier
Equal-i-zer WDH (10k), Prodigy Brake Controller