I ran through the gambit last year doing an ATF w/ filter flush, power steering flush, throttlebody cleaning, PCV cleaning, Oil w/ filter change, Front/Rear diff fluid change, Coolant change, spark plug change (this sucks on the H6 due to the frame rail clearance to the rear-most plugs), brake fluid change. Do these and your H6 will rock like it just rolled off the showroom floor. I get 25MPG now.