Have a 2000 Jeep Cherokee Sport. New to me. Manual said,s it is unnecessary to add anything to gas. Present gas has enough cleaning material in it to keep things just fine.

Can you use fuel injector now and then?

how about dry gas in winter?

Use synthetic oil, I use Castol GTX 10W-40(or 50).
Techron in the gas tank once a year (we use that at the dealer).

Best regards.

When I had mine I never put any additives in the tank. It ran fine on 85 octane the whole time I had it, winter or summer. If you going to put anything really powerful in it to clean it out put in BG44K. Great stuff and cleans everything! I always put valvoline oil in it and kept with the OEM sparkplugs.

Love that 4.0 I6!