Honda MDLA / MDMA / MT4A

4-speed automatic · transverse · 1994–present

Also known as: mdla, mdma, mt4a, bdga, honda 4at, honda 4-speed automatic, s24a

Honda's four-speed automatics — MDLA, MDMA, the Civic's S24A and the codes around them — in Civics, CR-Vs, Accords, Odysseys and the Acuras built on them.

⚑ Honda's automatics are not conventional planetary gearboxes. They use parallel shafts and clutch packs, laid out much more like a manual with hydraulic actuation — so a technician's planetary intuition does not apply, and neither do the diagnostic shortcuts built on it.

The consequence owners meet is judder and slip in third gear, the failure this family is known for, and it is clutch-pack wear rather than a band or a solenoid. Honda extended warranties on these for exactly that reason.

Fluid is the single largest factor and Honda's ATF-DW1 is not interchangeable — a generic ATF produces the judder early and is behind a large share of reported failures. A drain and fill is specified, not a flush.

The H5 five-speed that followed shares the architecture and much of the behaviour, and has its own page here.

Cars fitted with this gearbox

2 generations. Only where a source names the model and the generation together — a gearbox is documented as a product far more often than as a fitment, so this list is deliberately shorter than the truth.

Honda

Information, not instruction

CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.

Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.

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