Just as a heads-up (don't want to derail) don't fall for the hype that is the E3 plugs. I am running them in my Jeep now and have not noticed anything different. Have had them in for two tanks and no improvement to MPH, idle, or general operation. I am always a sucker for this kind of stuff and it doesn't matter how many times I get burnt. . . Stick with the recommended plug.

 

They are Bosch Double platinum (which actually have four arc towers on each plug) not E3s guy at pep boys said these are the best, and theyt could not get e3s

 

Other than pulling the drain bolt in the transfer case I dont think there is a way to check, you could pull the fill bolt and use a zip tie or something but I dont know if that would work. Check your skidplates and stuff, if they look beat up and scratched the previous owner more than likely wheeled it a bit. If all else fails go to the dealer and ask them if they changed any of the fluids before they sold it to you.

 

There nothing really to check, its not the level* so much as the quality of the ATF+4. By that I mean is it burnt smelling, cloudy/contaminated, unusual amounts of metal flakes or bits. Stuff like that. For the trouble of getting down there to check it, just change it.


*(yes, if the level is low you have a problem but that probably means a leak or crack or something but I am assuming the T-case is intact and functional)