guy plesase this thing is still funny and confusing to me cos i synonymize gearbox oil checking to engine oil checking but why is it that people say the right way to check gearbox oil is while the engine is running? is it true? is it while engine is running or engine is standing that you gauge for gearbox?

yes, in case of Automatic Gear you'll start the car, put Gear "D" and the mechanic will check the oil level using the correct gage for your car model

For gearbox oil, u guage when the engine is on running mode and gear is on D, for engine oil u guage when the engine is off and cool.

Pls my ppl i strongly did not believe your options,i do believe you start your car and ur gear should be on P then u can check if its gauge and very clean as the transmission oil u put was.If its short pls its not about topping it,All about how come its short cause its should`nt be.And if its smells or have some particle inside and ur gearbox still perform well then contact ur mechanic to drain the old oil and put a new Transmission gear oil.

Gauge transmission fluid while engine is hot and run through all the gears.
Park on level surface of course.

Depends on your manufacturer.

Some car with dipsticks require you check running warm on level ground with car in Neutral

Guess what happens when you go check your fluid with engine running in drive

Some cars don't have dipstick for transmission.

Here is the rule, apart from engine oil, Freon, and coolant that gets burnt off; if your car leaks find the source know what it is.

If your Transmission is not leaking, just follow manufacturer's guide using correct fluids.

So if your car has 100k miles on it first service should have been done at 60k miles(?) so you can start with a service now, or do drain &refill trans fluid(basically change 1/2 fluid) then repeat as needed.

Some people suggest drain & refill every 30k miles service every 60k miles(50,000&100,000km)

Most drivers will not driver a car for 50,000km in Naija, if a killer pothole does not get it first a rouge mechanic,okada, danfo persuade you to get another. I have not seen one owner put 100k on one car.