[cardoc]

Plugs aren't due but every 105-115k miles. The OE plug is an NGK with heat range 6. There's only one plug that really fits with this heat range and its NGK.

The hesitation could be a dirty throttle body. Could be just a lag in re engagement of the TCC. When you are in 3, you are at a higher engine rpm and the TCC is not engaged, so the reaction from throttle is going to be different. In D, the TCC lets go when you let off the throttle to relieve engine load and there will be a short lag in the time it takes for the fluid to pressurize against the clutch again.

Check your trans fluid level and if its been over 50k, its due for a flush and filter anyway so you can have that done and see what happens. Trans fluid breaks down and the pressure will change over time.

 

[cardoc]

I think the schedule says 60K but when I pulled my plugs at about 64K, they looked like they'd go another 20-30K easily. Maybe there's a lot of oil seeping from the tube gaskets and shorting the high voltage?

The NGK plugs for the H6 are iridium tipped and tend to last upward of 100k. 60k is severe use recommendations. Transmission fluid is recommended every 30k with severe use, i.e. high temps, towing/hauling, etc. If its an easy daily driver, you can go 50k on the trans.