Originally Posted by roy'sz

The type of driving you want to do is what decides when you shift. Lets say you want to get really good mileage out of your car. Barely depress the accelerator (it takes almost no throttle to get our cars moving) and shift around 3k. With that easy type of driving and shifting you should see close to 25mpg. Now burry the throttle and shift at 7000rpm's and you should be seeing around 17 mpg. It just depends on your driving characteristics and ofcourse your driving route. I avg 21-23mpg on my tanks due to the fact that I work night shift and I catch almost no traffic coming home. I have light traffic in the afternoon but I am not that hard on the throttle. I changed out my factory trans oil at 30k and noticed that shifting had improved by about 30%. I also flushed my clutch fluid and regularly change the sump out so it stays fresh.