Janet -

The rear axle ratio is different between manual and auto, with the auto having a 3.73 ratio and the manual having 3.31. The higher number gives more pick from a standstill, the lower gives lower revs at cruising speeds. The auto 3.73 is to compensate for the loss of instant pickup due to the torque convertor.

Rich said if sitting a while at idle pop it into N. Good idea, keeps the trans cooler and reduces wear.

The gearing and shift points are set up for a smooth ride, not for drag racing. If your car has a tachometer you can enjoy "manualizing" the shift points. Start in 1, run up to 3500 to 4000, move to 2. Run farther up, go to 3. Let it choose when to shift to overdrive.

Do this for quicker pick-up, as in merging from a dead stop, etc. At 3500 in 3rd or overdrive you will be up to or beyond freeway speed.

My town, Houston, is flat as an ironing board. With no hills, the overdrive cuts in just over 40mph. It's easy to see the tach drop down. The o/d allows the engine to spin 20% slower than the drive shaft. In 3rd they spin the same.

The o/d button on the gear handle gives a way to kick down without flooring the gas pedal. I find it nice to use for a little burst of power when changing lanes or overtaking a slower thing or climbing an overpass.

BTW, if you do not have a tach but want one, they are sometimes found on eBay or you might check salvage yards. It will go right where the large clock is, and you get the 2-inch clock and harness to go to the right of the instrument cluster. The tach wire is put in at the factory. It is a DIY job.

Enjoy your ride.

Good Luck,

Bob

:>)