I have the RFE trans as well, this is my 2nd vehicle with that transmission. Advise changing the fluid & filters in that at 60k miles, definitely not later than 100k. It's not a delicate box just neglect and abuse will kill it same as anything. Don't slack on the other fluids like brake fluid shouldn't see 10 years, coolant really you should strongly consider changing it at 5-6 years even though it's "10 year" coolant. The anticorrosion additives get used up as time goes by so it's good to get out ahead of that. Don't wait for your dashboard to tell you it's time for an oil change, don't let the transfer case or axles see 100k miles or 10 years with the original sauce in them. ~60k is a better idea for the rear if it has the anti-spin LSD in it, especially if you put it to work a lot (slippery winter roads, etc)
Beyond the fluid maintenance stuff the most important factors in longevity are keep everything clean top to bottom, fix things when they start to show signs of breaking not 6 months after they catastrophically failed, and don't just randomly throw "mods" on like they're Pokemans you gotta collect. That's about it. Clean and waxed paint doesn't gather oxidation and scratches. Clean metal/paint don't retain moisture to accumulate rust. Clean seals/gaskets/wires/hoses don't deteriorate as fast as oil-and-gunk-soaked ones. Plus troubleshooting on clean stuff is infinitely easier than on dirty stuff and repair is easier as well.