the search feature could have helped, plus there are some interesting/informative discussions buried into this thread, so if you get some time and a good internet connection, do go through the previous posts, hopefully it would be worth it, but unfortunately a lot of topics are discussed over and over again, which also made a very senior member (sameer bhai aka storm) mad at the ppl posting such things and he does not feel like posting here any more.
Yesterday I went to Toyota Workshop in Aabpara Islamabad, they are really ripping off people just for example they quoted me the Price for the Front Brake Discs as 7500(for new model) and 5310 Rs (for older models 99-2004), where as a spare parts dealer quoted me the maximum price for the genuine ones to be 1700- 2000 for the older shape...
they were charging 4000 for just checking the Car on Computer.
I called Toyota walton motors the other day, and they quoted ~4k just for the front brake shoes
The person told me that when driving within city keep the "O/D OFF" light ON, and with this setting the car will go only upto third gear.
and while driving on longer routes where higher speeds are required turn the "O/D OFF" light OFF, and the car will go upto the fourth gear.
now you know what o/d is, i believe you can decide when to use it. i personally believe that its okay to let the car go to 4th gear and get better fuel economy, and if you need more power, the moment you press the gas pedal (at 60-70 kmph) the car will automatically switch to a lower gear, and there won't be burden on the engine or knocking, the car is intelligent enough to handle it