Originally Posted by triethylborane

Plugs should be changed when the gap is out of spec or if the spark plug is faulty; to make these determinations requires pulling plugs and given plugs are cheap, usually makes sense to pull them with the intent to replace on a 86k mi vehicle. Get Denso.

Coolant can be tested with a cheap tester from any parts store. If its not been changed . . . it probably needs to be changed. The "Asian" red formulation from Zerex or Peak are cheap and work well.


Trans fluid is something I change at 70k miles or so and Ive not seen evidence that lifetime fluid is anything but perhaps lifetime of a lease or such. Go with the Toyota WS stuff