My Rodeo just passed the 120K mark (bought it @ 109K) and I'm building my to-do list for the weekends this winter. I've already replaced all of the brake pads/shoes and shocks as they were shot from the first moment. Cleaned out the EGR to stop a check engine fault. Also, I've replaced the PCV, air filter, serpentine belt, battery, and balanced the tires. I have a timing belt job and seafoam flush of the intake already in the queue.

Should I flush the tranny (automatic) and replace the screen?

Rear diff flush?

Spark plugs? What's the best replacement for my 3.2L V6 DOHC?

What are your thoughts on 'off the shelf' fuel system cleaners/additives (fuel injector cleaners)? Do they work and if so what's the best brand to use?

Other suggestions?

This thing runs perfect and I want to keep it that way through the 200K mark!

Dont know what kind of maintenance your tranny has had but if it hasnt had regular fluid changes then dont flush it. That would most likely kill it. Just drop the pans clean/replace the filter and refill.

I used denso double platinum plugs in mine. I've always been a big believer in denso plugs and have had no problems with them.

Diff fluid changes would be good. Should be done every 30k miles. Front wheel bearing repack/replacement maybe.