Advice wanted on changing auto gearbox oil/filter 1KZ-TE 3l

I'm in Portugal, it's very hot (40C), and I've started to get an ominous burning smell after driving in the mountains. Could be the brakes...but I'm thinking more likely the auto gearbox oil is old & needs changing. Could some kind person give me an idiot's guide to doing this? Where to find the drain plug, filler & filter, what kind of oil to use & how much, etc? Many thanks.

First check the level, the fluid should be red and not smell of anything. If it is low, checked by having the engine hot and moved through the gears placed in park with the engine running, look at the colour is it brown/black or does it smell of burnt toast topping up will not have much of an effect.

Sump drain plug underneath box, square 14mm if I recall correctly.
Filter is inside the sump which needs to be removed. Silicon sealant needed to refit. It is just a fine gauze that needs washing in clean fluid.

Refill via the dip stick tube.

The sump will hold 2 - 3 liters, the remainder of the fluid is on the Torque converter and the channels of the box. I do two or three sump drains over a few weeks to get the fluid back to red.

There are more technical ways but if you stick to the above you can't go too far wrong. A fluid change on a garage machine costs around £100 in the UK. They connect to the fluid cooling pipes sucking out old and filling with new until the old comes out clean.

Hope this helps.

Clive, many thanks indeed for that useful info (& apologies for not thanking you sooner – I'm not able to get online very often & I didn't get the usual email notification of a reply, so I've only just picked this up). I haven't done anything yet, except check the oil level & quality, hot as recommended – the level is fine and the fluid looks red and feels quite sticky, which I guess is good. The symptoms I still have though are, occasionally after a long, steep hill climb in the heat, I get a definite 'burning clutch' type smell. I stop & let things cool down awhile. I can't think that this could be anything else but the gearbox, unless you have other ideas? I may just go to a garage here & have the fluid changed (labour is cheap here, so may not be too expensive). What particular fluid do I need? I understand it is different for older boxes. My Portuguese is not good so I want to be able
to be sure they use the correct stuff!

Is the SC a turbo.If so that may be another problem worth investigating

Hi, yes it is. How would i know if that's the problem?

i am no mechanic but I thought that maybe with the turbo operating hard it could have had an adverse effect on it seeing that oil is lubricating it and the turbo needs to cool down for several minutes with the engine running at idle .Maybe someone on here could enlighten you more than I can about checking it out.