What Happens If ATF Fluid is Added toa CVT Transmission - Vol.349
For the longest time automotive transmission fluids are known as MTF for manual transmission fluid and ATF for automatic transmission fluid. It would all change in the past decade or so when new technology allowedcontinuously variable transmission (CVT) to be used in cars other than those with small engines, which is when CVT began to show up in force in major car brands like Honda, Toyota, Nissan, Audi, Hyundai, etc.
A Hypothetical Question
The question of what happens if ATF fluid is added to a CVT transmission or CVT fluid is added to a conventional automatic transmission gearbox is a bit hypothetical in nature. First of all, conventional ATF fluid is red but CVT fluid is green ? for distinction and for the fact that all car makers want to make US dollars which are also known as greenbacks.
Even more crucially, most modern cars do not make it easy for consumers to change transmission fluid on their own. A Nissan transmission dipstick is for you to check the fluid level but not really for you to add transmission fluid into the small dipstick hole ? because you really should bring the car in for a checkup if the transmission fluid level is low. Almost all higher-end cars come with sealed automatic transmissions ? there is no transmission dipstick or any other way to check the transmission fluid level at all because the companies believe, rightly or wrongly, that the transmission box would last the lifetime of the car.
When Hypothesis Became Reality
If the unthinkable happened and ATF fluid was mistakenly added to a car's CVT transmission, it's more likely to be done by a careless or clueless mechanic than by the car owner. It is doubly unfortunate that the owner of the car would probably not be able to a tell a difference?c until one day in the future, which is likely to be much longer than days or weeks, the CVT transmission fails and he or she finds out why.
ATF fluid is used to lubricate and actuate a more primitive transmission that basically consists of a hydraulic pump, a set of gears, clutch discs and bands. It is not going to do the job with CVT transmissions that are gearless systems of chain-driven or belt-driven conical blocks or pulleys or discs and rollers.
CVT transmissions need CVT fluid which also contains friction modifiers that provide the proper friction needed for the chain or belt to grip and drive the cones, or the cones would just wear out over time. The car with CVT transmission will still work for a period of time because it is impossible to drain all the CVT fluid. So when a mechanic mistakenly adds ATF fluid to the CVT transmission, the transmission would contain a mixture of CVT and ATF fluids.
There will still be enough friction provided by the remaining CVT fluid for the CVT transmission to work for a while until eventually the whole transmission needs to be rebuilt. How long the CVT transmission will continue to work is believed to be a function of how much CVT fluid is left in there. You should be able to continue driving the car for longer with a 50:50 CVT/ATF mix than a 25:75 mix, but in both cases there will be permanent damage done to the CVT transmission. Failure is only a matter of time unlessperhaps if the problem was caught and corrected in good time.
There is good news! Now that you know what not to do, hopefully this will never happen to you.