wichess

Steering pump is dying or already dead, more likely due to running dry witout PSF. You should have topped up PSF long back to save pump.

If there is a leak in AC system then freon (AC gas) leaks and spoil the cooling, you need to top up AC gas but before that let qualified guys find the leak and fix it first and then top up gas.

Looks like shock absorber need change there, better show to qualified technician before jumping to conclusion as its slightly expensive to change all 4 shocks.

If any or all not working then u got to change, else TPMS valve stems have no life issue. They are good for 3-5 years least.

Show to local electrician and ask him to pull apart the up and down option (if its separate) then u can buy same from Divya and Dhanya if the part is same as GCC spec. I assume ur 2004 GS400 is from US. If not source same part from US and get it here thru aramex (cheapest courier)

There is no specific brand per series. Toyota same or may be 2 types of battery for cars with different sizing and amp need. You can also check AC delco and amaron battery, they hold good value for money and last reasonably long.

hey i need to replace the Knock sensor of my 2008 GS300 a video or a diagram will also do. thanks