What are the Toyota Celica GT4 ST165 engine and gearbox fluids

If you put the wrong fluids in then you may well shorten the life of your car and/or cause some engine damage.

That's up to them. Listed here are the recommended Toyota specifications for your engine. Personally, I think Toyota have more than enough experience and skill with engine design, development and maintenance to say what should be used in their engine. Opinions vary...

What fluid?	Specification	My 2p...	When to change?	Capacity (Litres)
Petrol	95 RON or higher	Use this as a minimum specification The higher the RON the less chance of detonation...		60
Engine oil	Graded - SE, SF, SG or better Viscosity dependant upon ambient temperatures	Get a decent oil... I use 10W/40 Always change the filter along with the oil Do not use Magnatec Semi or fully synthetic only	5000 3000	3.6 ~4.5
Engine coolant	Ethylene-glycol or alcohol type	Use the expensive Red Toyota Long Life coolant I have seen extensive "furring" up of pipes and sensors when something other than the Toyota coolant has been used in these engines...beware!	Ethylene - 40,000 Alcohol - 20,000	6.4
Intercooler coolant	Ethylene-glycol	Use the expensive Red Toyota Long Life coolant Warning as above!	Ethylene - 40,000 Alcohol - 20,000	1.6
Gearbox oil	Grade API GL-5 Viscosity dependant upon ambient temperature	I use 75W-90	Checked - 15,000 Changed - 30,000	5.2
Rear differential oil	Grade API GL-5 Viscosity dependant upon ambient temperature	I use 75W-90	Not specified! 30,000	1.1
Clutch fluid	DOT 3	I would use DOT 4 as this is a higher grade Don't use DOT 5 it's a lot different to DOT 3!	Not specified!	1.5?
Brake fluid	DOT 3	I use DOT 4 as this is a higher grade DOT 5 isn't recommended as it's a lot different to DOT 3! DOT 5.1 might be an alternative	40,000	4?