Is 20w 50 engine oil okay with my vehicle and how frequently should I have an oil change. I stay in Nigeria. We have a relatively hot climate
No. Don’t use it. Hotter weather/thicker oil? Is a myth.
Does your car overheat? Cooling system is ok? Why then do you think it is heat stressed?
Do you remove the thermostat to make it run cooler?
This is covered in your owner’s manual. I suggest that you stick to those instructions.
If you have a large displacement push rod engine that oil would likely be OK but any late model DOHC variable valve timing engine almost certainly needs a lighter oil.
I agree with Rod-Knox that 20/50 would work on an older vehicle but not so well on a later model car.
Even with an older car I would never run 20/50 in a cold climate. It turns to the consistency of cold tar.
I would guess the recommended oil is 5/30 or 10/30 all depending.
How frequently you change the oil depends upon the type of driving, dust, humidity, state of tune, engine wear, gasoline quality, and so on.
My Harleys use straight 60 weight and on a cold day one might as well leave the oil container in a funnel and go watch a football game while it drains.
Long ago a fleet owned V6 Ranger was towed in with a seized engine. I dropped the pan to inspect and found the oil pump drive shaft wound up like a cork screw and resting in the pan. The temperature that day had been down to single digits which is unusual here and the oil was as thick as molasses. When I called the fleet manager he checked and found that the department that operated that truck did their own oil changes occasionally and the driver had replaced the oil with Castrol 20W50 + a can of STP. I can assure anyone who is curious that combination is not suited for cold weather.
2003 Camry owners manual recommends 5w-30 for all conditions.