Reconditioned Abarth 500 1.4 T-Jet Gearbox

Abarth 500 1.4 T-Jet Gearbox: why does the transmission give out before the engine?

On the Abarth 500 from 2008 to 2015, it is rarely the engine block that fails first. The 312A1000 and 312B4000 can take a beating, but the transmission takes the strain differently depending on whether it is the 5-speed manual or the MTA (automated manual gearbox with actuator). On the manual, the tell-tale symptoms are stiff gear changes in 1st and 2nd when cold, gear noise under load and, over time, premature wear of a gear or synchromesh ring — a direct consequence of the power concentrated through a compact city-car gearbox.

MTA: the weak point that symptoms can mask

The MTA shares its internal mechanics with the 5-speed manual but adds a robotised actuator. When gear changes become jerky, slow or erratic, the root cause may be mechanical (gearbox) or electromechanical (actuator). The MTA gearbox is sold without its actuator: if the diagnosis confirms internal wear, it is the mechanical unit alone that is replaced. Confusing the two causes delays diagnosis and leads to an unnecessary replacement.

312A1000 or 312B4000: the engine code determines the exact reference

Both engine codes exist across this 2008–2015 range and do not always take the same gearbox. Before placing any order, the code stamped on the block — not simply the engine capacity or the stated power output — is the only reliable criterion for identifying the correct reference from the five available in this collection.