Oil type

[DanTavensis]

Hi I have to Toyota Avensis 2.0 1az-fse engine. I’ve gone in put 0W 40 engine oil in, I know now that a spec of 5w 30 is required as it states in the manual, which I don’t have.

the motor oil I have in there is Mobil 1 with these specs

Will it cause my engine any problems running like this, I know the oil will be slightly thicker at higher temperatures which is what bothers me. Is this anything to worry about?

[Cessna]

Car manuals often specify a range of oil grades that are acceptable. So check to see if that is the case for your car, and then check if 0W/40 is within it. I have a T27 rather than a T25 so I can't help with your car, but if you don't have a manual I'm sure somebody with one will be along very soon.

[mrfixer]

It will be absolutely fine.

[Heidfirst]

the thing to be concerned about is that your engine is not compatible with the E10 fuel that is about to replace regular E5.

https://mag.toyota.co.uk/e10-petrol-what-is-it-and-can-i-use-it/

[DanTavensis]

I already know that that’s why are use as a esso supreme

[joyne]

You could try 5w-40

[NGRhodes]

The thickness is nothing to worry about, assuming the choice is between FS 0w40 and ESP 5w30
This 40w is on the thin side of a 40w, its close a thick 30w, (12.5 vs 11.9 at 100C) the difference is flow between the above 40w and 30w will be less than the difference between same oil 10c warmer/colder - well within usage tolerance for normal use (not in the artic or doing track days regularly). The difference will be 1 or 2% economy at most on a dyno rig, and less on a real world car test, probably lower than repeatability.
The important viscosity is the HTHS (which is a measure of metal to metal protection)  which is 3.5 vs 3.58 - which is close and higher than the minimum 2.9 required for both 40w and 30w, so both oils will offer better than the minimum protection required for the specs.