I just bought a new-to-me 1998 T100 with 100K miles on its 3.4L V6, and I'm a little concerned about its oil pressure. When hot, the pressure indications on the factory gauge runs very close to the bottom limits described in the Owners' Manual.
I'm currently running 5W30 oil per the manual for the Southern California temperature range. Can I go to a higher viscosity (10W40?) without doing damage?