mrfixer

Please post up your emissions test results.

The U340/341/E was a popular transmission used on Avensis, Corolla, Celica etc. It is easy to obtain parts for rebuild - a complete seal/rebuild kit is about £200. You need someone with experience to do the work. With a high-mileage 2005 car it is probably better to fit a secondhand gearbox.

For C50 transmission its a 75W85 or 75W90 to GL4 or GL4 & 5

This can be due to 'cupping' of the treads - an uneven wear pattern that generates a humming noise. Ideally you should rotate the tyres every 5000 miles or so to even out the wear.

GL-5 LS means that the oil has friction modifier additives for limited slip differentials. Your Avensis does not have a limited slip differential. I doubt using it would cause any damage but possibly the gearbox synchro would not perform optimally.

Most Toyota manual gearboxes take a GL-4. What is the engine series code on your car?

Personally I would put a 75W-80 in there. You'll get much smoother low temperature shifts and less baulking on downchanges. Make sure its a GL-4 oil and NOT a GL-5.

Either a coolant leak somewhere or head gasket problem. Best bet it to take it to a garage and ask them to pressure test the cooling system.

IIRC Tax is a bit higher on the T25. The 1.8 Valvematic on the T27 is a little more economical than the T25 1.8, but not a huge amount in it. The T25 is a slightly simpler car and there are huge amounts of inexpensive secondhand and aftermarket parts available.

2010 is T27 series. 2006 is T25. T27 drives nicer - its more modern. Its also more complicated (electronic parking brake and Valvematic engine). T25 is simpler. Will be cheaper to run. Watch for rust at that age. 2006-2008 1.8 petrol engine is pretty much bulletproof.

You've put the bulb in wrong and blown fuse no. 14. Its a 10A fuse. Fuse box is inside the car at the left side of the dashboard (behind glovebox on a RHD car).

5W is sidelight 21W is DRL.....

A 'poke and hope' approach is not the way forward. Get the codes read by someone with appropriate equipment - ideally Techstream. A flashing light is usually a pollution control fault - ign system, O2 sensor/injector fault etc etc..

Daytime Running Light I would think...

Its the A/C condensate drain pipe. Nothing to worry about.