Correct Fluid Will Help in the Clutch

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Times Staff Writer

Question: On several occasions you have covered various types of motor oils, but how about transmission fluids? Recently, I purchased a Lincoln Town Car with automatic overdrive transmission. Ford calls for it to use Dexron II fluid, Series D, and gives a Ford part number. For years, I have been using Dexron II M2C33-F Type fluid in Fords. Can you help with some information on the proper type of transmission fluids?--A.E.S.

Answer: Motor oils are a relatively simple issue compared to transmission fluids. Ford alone has three different fluids that it specifies for various model years of its cars.

How important is the right fluid? It’s critical to the longevity and proper function of an automatic transmission, according to Norm Hudecki, a Valvoline oil expert. Some automatic transmissions require what is called friction-modified fluids; others require non-friction-modified fluids.


Used correctly, the friction-modified fluids provide smoother, quicker shifting. They contain sulfur-phosphorous modifiers that allow clutches to slide rather than grab. But they should be used only where specified by the manufacturer. One type of friction-modified fluid is Mercon, which is recommended by Ford for only some of its cars.

Here’s the tortured history. Ford recommends M2C33-F for 1977 and earlier transmissions. It recommends M2C138-CJ for model years 1978 to 1982, M2C166H for some models between 1982 and 1987 and M2C138-CJ for other models. Fortunately, this has been somewhat simplified by the introduction of Mercon fluid for 1988 cars and other models that formerly used M2C166H and M2C138-CJ. It’s important to note that M2C33-F is a non-friction-modified fluid and cannot be replaced by Mercon.

All General Motors cars can use Mercon, according to Hudecki. Most Chryslers take Mercon, but some 1987 and 1988 rear-wheel-drive Chryslers do not.

Q: A group of us are puzzled over the reason for the kind of ignition lock that won’t release the key until a button or lever is depressed. I have asked around and can get no reasonable answer. Can you clear this up?--P.A.C.

A: Federal motor vehicle safety standards require manufacturers to design the ignition lock so that it is not easy to remove the key and thereby lock the steering column while driving.

The various manufacturers have taken different approaches to this safeguard. Some require the motorist to push in and rotate the key by almost a half turn. Others, such as Toyota and Ford, incorporated a button that must be pushed simultaneously.