Ford FNR5 slipping or no reverse hot - Transmission Digest

Ford FNR5 slipping or no reverse hot

The complaint

A Ford vehicle equipped with the FNR5 transmission has a complaint of a severe slipping condition in reverse. As the transmission approaches normal operating temperature, reverse movement is non-existent.

The cause

The case is cracked behind the low reverse clutch apply piston in an obscure area. The crack can be very difficult to see if it doesn’t spread (see Figure 1, above).

The correction

It’s simple: Replace the transmission case.

Read more articles in our Transmission Tech/Talk series here.

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