Mazda F-series automatic (F3A / FS5A-EL)

Mazda's 4EAT family — the four- and five-speed automatics behind most front-wheel-drive Mazdas from the late eighties, and behind a good many Fords.

⚑ Ford owned a large stake in Mazda when these were designed, so the same gearboxes appear under Ford codes — the CD4E and 4F27E have pages here and are the same lineage. Searching the Ford code often finds material the Mazda code does not.

The -EL suffix means electronically controlled, and the generation split matters: the early F3A is hydraulic, and nothing learned on it applies to an FS5A-EL.

Their characteristic complaint is a harsh or delayed 1–2 shift as the fluid ages, and Mazda's specified fluid is not interchangeable with the generic ATF most shops reach for. That substitution is behind a large share of reported faults.

The JF506E is a Jatco unit sold under a Mazda code (JA5A-EL), which is worth establishing before ordering: it is a different gearbox from the rest of this family.

F3A is a three-speed and the FS5A-EL a five, with four-speeds between them. The family ran for twenty years and the ratio count is the quickest way to place an example in it.