2026-09-22 · 4 min read
Manual Gear Oil vs ATF vs CVTF: What's the Difference?
Manual gear oil, ATF, CVTF and DSG fluid all look like gearbox oil but they're completely different — using the wrong one can destroy your transmission. Here's how to tell them apart.
Manual gearbox gear oil
Manual gearboxes use gear oil (75W-90 or 75W-80), which is much thicker than ATF. It contains extreme-pressure (EP) additives to protect metal gear contact faces and helps the brass synchros mesh smoothly during shifts.
Spec is usually GL-4 (most manual petrol cars) or GL-5 (some 4WD differentials). Important: GL-5 is not suitable for most manual gearboxes because its high EP concentration corrodes brass synchros.
Automatic transmission fluid (ATF)
Automatic transmissions (conventional torque-converter type) use ATF, which is completely different from gear oil — very low viscosity (similar to hydraulic fluid). ATF also transmits hydraulic power, cools the transmission internals and lubricates shift solenoids.
Common specs: Dexron VI (GM), Mercon V/LV (Ford), Toyota WS (Toyota-specific), Honda ATF-Z1/DW1, Aisin ATF, etc. Different specs cannot be freely substituted — always use the manufacturer's specified type.
CVT fluid and DSG fluid
CVT (common in Myvi, Bezza, City, HR-V) requires dedicated CVTF — completely different from regular ATF. CVTF must deliver precise friction between the steel belt and pulleys; using ATF instead causes the belt to slip and can destroy the transmission. Never substitute ATF for CVTF.
DSG/DCT dual-clutch (VW, Audi, Porsche) requires dedicated DSG fluid (e.g., VW G052529) and also needs a Mechatronic unit service — it's not a simple fluid change.
What happens if you use the wrong oil?
Consequences range from poor shifting to complete transmission failure — a CVT that received ATF may start slipping immediately; a manual gearbox filled with ATF will shift poorly and can damage synchros. Repairing a damaged transmission costs far more than the oil change.
Not sure what your car uses? Check the owner's manual, or come to 4M Car Care — we know the correct fluid spec for every brand and model. WhatsApp to ask.