Bought a used 09 with 19k on it. Carfax/Nissan dealer doesn't show anything for the 18k maintenance being done. Service indicators on the display say I need to do the oil change, but the 2nd one for "general" says I'm a little over 2k into 18k service indicator. Is there any way to check if the diffs/Transmission fluids have been changed? Or should I just do what I'm planning to and get the service done at nissan to be on the safe side?