Nissan Repair: brakes & tune up, master brake cylinder, gas mileage

Question
QUESTION: The o/d button or over drive button
-what does it do
-when is a good time to use it
-should it always b off or on
-how do u knw its working right

Cruise control
Same questions as above.

Oh how do u tell which model of maxima it is I have a 96 maxima I would like to know if it is a se,sle or gle or something like that all I knw is mines is automatic I don't know what model

ANSWER: Myra,

The overdrive (o/d) is vital for gas mileage and to keep the transmission from failing.  It is supposed to default to the on position when the car is started.  It should always be on.  Only time it would be off if you were climbing a hill and the car keeps kicking in and out of overdrive.  If that were the case turn it off until you get over the hill.

Cruise control is just for when you are on a long drive, on the highway, and you do not want to keep your foot on the gas to maintain speed.  If you are driving where it is congested and you cannot maintain a decent space from other cars tap the brake to turn it off and just use your foot.  

The type of Maxima is on the trunk.  If it is an SE, it is the sport, no difference in the engine and just a small wing on the trunk to make it look cool.  Some additional stuff to give you a sport feel.  

GLE is the one with all the goodies like leather and the like.  Interesting that there is no difference in engine so it is just a matter of what goodies, like leather, sunroof and the like you have.

---------- FOLLOW-UP ----------

QUESTION: Okay my brake fluid is leaking out very slowly. Its not leavin a paddle but every 2 months or so I have to put more brake fluid into the master brake cylinder and it doesn't get empty jus a lil low. The master brake cyliner was chanhed in december so its not that I would like to know do I need to change the brake lines or the brake hose. The last time the brakes were bleed was a january n still the same problem

I'm sorry for all the questions

But also what is everything I need done for a complete tune up and exactly what do I need to buy for the tune up??

Answer
Myra,

If there is no fluid on the ground and it takes a couple of months for the fluid level to drop would mean as the brake pads wear the pistons, in the calipers, push out allowing the fluid to drop in the master cylinder.  This should be normal.  

A complete tuneup would include the following:

Plugs
Wires
Distributor Cap and Rotor
PCV Valve
Air Filter