The AWF21 Transmission: Here Are A Few Things All Shop Owners Should Know

Posted by on Monday, April 15th, 2013

The AWF21 is a six speed automatic transmission. It is designed for use in traverse engine applications. This transmission is unique in that it is designed by Aisin, a company that builds transmissions, and not by an individual automobile manufacturer. It is used in a very wide range of vehicles including Alfa Romeo, Cadillac, Citroen, Fiat, Ford, Lancia, Land Rover, Lincoln, Mazda, Mercury, Opel, Peugeot, Range Rover, Renault, Saab and Volvo.  It also goes by the name of TF-80SC. It is a light duty transmission designed to withstand a maximum of 320 ft-lbs of torque. What makes this transmission special and so desirable to a wide range of manufacturers is that it is very small in size. It was designed from the start to fit into the space of a manual transmission. That makes it a very small transmission, indeed.

The AWF21 transmissions

Source: 2car

Because of the wide spread use of this transmission, it is important to know a few important details and failure points associated with it. Here is what to look out for.

There has been, in the past, a lot of complaints about harsh shifts, especially when the transmission is hot and under full power.  The complaints have been that the transmission shifts too hard at times. The factory is currently addressing the problem by replacing the entire valve body. The problem most likely stems from a stuck valve or warped valve body.

The valve body in the AWF21 can be problematic


The fluid designed for us in the AWF21 is called AW-1 fluid. It is designed to last the life of the transmission. My recommendation is to ignore the advice of the factory and replace the fluid every 20,000 miles. I just can’t see how that fluid can go a full lifetime without being contaminated by normal wear from within the transmission.  You should also replace the transmission filter at the same time you replace the fluid.  Be very careful on the choice of fluid you put into the AWF21 transmission. Use of the wrong fluid (those other than the AW-1) has been known to cause problems, too.

The AWF21 seems to experience more computer issues than other modern transmissions. A common problem (at least according to Ford) is that hesitation may occur when accelerating. It usually only happens when the transmission is cold. The cure it to reprogram the computer using patches provided by the manufacturer.  There are many other problems associated with the computer, too. So many that we just can’t list them all. If your customer’s transmission is acting up, the first thing I would do is conduct a computer scan, followed by a hard reset.

Cut-away view of the AWF21


The AWF21 is a better than an average transmission, but it won’t last forever.

When the time comes to replace it, convince your customers to spend their money wisely and invest in a re-manufactured transmission. A re-manufactured transmission is every bit as good as a new transmission, but comes at a much more affordable price. It will also most likely include modifications to make it last longer, something the factory should have done in the first place. A re-manufactured transmission also usually comes with a much better warranty, too. Three years compared to an average 90 days for a rebuilt transmission.

One Response to “The AWF21 Transmission: Here Are A Few Things All Shop Owners Should Know”

  1. EARL DAVIS says:

    Where is the filter located on the Aisin F-21?

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