The BC-series manual transmissions are a series of manual transaxles produced by Ford in Europe for its front wheel drive automobiles from 1976 onwards. Originally debuting in the Mk.1 Ford Fiesta, the unit was later used in Ford's other front wheel drive vehicles, most notably the Ford Escort and Orion.
The unit features a 20mm x 17 spline input shaft, uses a rod-based shift linkage and was originally only available in 4-speed format, designated as BC4, and designed to mate either with the Valencia version of the OHV Ford Kent engine, or the CVH unit. The 5-speed BC5 version appeared in 1982 on the Escort as a standard fitment on 1.6 litre cars, and as an option on 1.3 models.
A completely revised version of the transaxle was introduced in 1995 and was designated iB5, and was initially introduced for the Mk.4 Fiesta. The major difference being an improved cable-operated shift mechanism and the introduction of a hydraulically operated clutch. The ultimate version is IB5+, manufactured only in Brazil, that fits engines as big as 2.0 litre.