The IB-series manual transmissions are a series of manual transaxles produced by Ford in Europe for its front wheel drive automobiles.
The original version (IB4) was a fully synchronised 4-speed introduced in 1976 for the first generation Ford Fiesta. Following the introduction of the third generation Ford Escort, a five speed version (IB5) was introduced in 1982. The ultimate version is IB5+, manufactured only in Brazil, that fits engines as big as 2.0 litre.
The biggest change to the unit over its production run was for the introduction of the Focus in 1998, when the rod based shifting linkage was changed to cable operation, and the adoption of a hydraulic clutch mechanism.
Earlier versions of the unit have one weak area; the differential bearings have a tendency to break up after around 80,000 miles. If left unchecked, this problem can result in the driveshaft grinding away the gearbox casing. The first sign of this problem is the speedometer ceasing to function.