A/T - A4LD, 4R44E/4R55E Pump Interchangeability
DATE: 1996TECHNICAL BULLETIN # 335
TRANSMISSION: A4LD, 4R44E/4R55E
SUBJECT: Pump interchangeability
APPLICATION: Ford, Mercury
A4LD, 4R44E / 4R55E
The A4LD has gone through many changes. One of the latest changes is that it is fully electronically controlled. Another major change is the redesign of the pump housing, pump gears, and bell housing. There is still interchangeability within the units as long as the entire assembly is used. Mixing parts will cause a failure due to changes in the lube circuit. The following illustrations show the difference in the parts.
Bellhousing
Pump Plate
Pump Body
Pump Gasket
Pump Gears
The pump gears are the same diameter, however, they are not interchangeable.