ZF 4656.275.018 for WG160 | OEM Genuine Part

Overview

The ZF 4656.275.018 is a critical OEM genuine component engineered specifically for the WG 160 Series transmission. This part functions as a precision-machined adapter or support element within the transmission’s hydraulic control system, ensuring correct oil flow and pressure regulation during gear shifts. The SKU 4656.275.018 sits between the main valve body and the rear housing assembly, acting as a sealing and alignment interface that prevents cross-leakage between circuits. Without this genuine ZF part, the transmission cannot maintain proper clutch engagement timing, leading to performance degradation under load.

Symptoms of Failure

• Delayed or harsh engagement when shifting from neutral to drive — A worn 4656.275.018 causes inconsistent hydraulic pressure, resulting in a noticeable lag or “clunk” during gear selection.
• Intermittent oil seepage around the rear housing joint — As the part degrades, internal seals lose their integrity, producing slow drips of ATF fluid near the HOUSING REAR PART interface.
• Erratic shifting under moderate acceleration — The transmission may momentarily slip between gears or hunt for the correct ratio when the 4656.275.018 fails to regulate pilot pressure.
• Visible metallic debris in the transmission pan — Advanced wear of this component generates fine aluminum or steel particles that contaminate the fluid and clog the SCREEN SHEET filter.

Technical Specifications

Parameter	Value
OEM Part Number	4656.275.018
Material	High-grade aluminum alloy (EN AC-44100)
Weight	0.85 kg (1.87 lbs)
Length	142 mm
Width	68 mm
Height	32 mm
Surface Treatment	Hard anodized (mil-spec)
Sealing Grooves	2x O-ring channels (ISO 3601)
Operating Temperature Range	-40°C to +150°C

Compatibility

This genuine ZF 4656.275.018 part is primarily designed for the WG 160 Series transmission family. It is also compatible with the following ZF models when used with the correct TRANSMISSION HOUSING and HOUS.FRONT SECT:

• ZF WG 160 (all sub-variants)
• ZF WG 180 (with adapter kit)
• ZF WG 200 (limited compatibility — verify housing code)
• ZF Ecomat 4 HP 590 (retrofit applications)

For proper installation, always pair this part with a new HOUSING REAR SECTION gasket set to prevent future leaks.

Related Components

Part Number	Name	Function
4656101077	TRANSMISSION HOUSING	Main structural casing for gear train
4656201102	HOUS.FRONT SECT	Front section housing torque converter
4656201103	HOUSING REAR PART	Rear housing for output shaft support
4656298063	HOUSING REAR SECTION	Complete rear section with bearing bores
0631306816	CYLINDRICAL PIN	Alignment dowel for housing mating
0750301002	FIXING PLATE	Retention plate for valve body
0636100817	CAP SCREW	M8 x 25 mm fastener for housing
4656301016	SCREEN SHEET	Fine mesh filter for oil pickup
4656301017	SCREEN SHEET	Coarse mesh pre-filter
0636100803	CAP SCREW	M6 x 20 mm fastener for valve body

Frequently Asked Questions

Q: How do I know if the 4656.275.018 needs replacement?
A: Inspect for visible cracks, distortion, or scoring on the sealing faces. If you observe ATF weeping from the rear housing joint after cleaning, or if shift quality degrades with no other obvious cause, replace this part immediately.

Q: Can I reuse the old O-rings when installing this part?
A: No. Always install new O-rings (sold separately) to ensure proper sealing. Reusing old seals will almost certainly cause immediate leakage at the HOUSING REAR PART interface.

Q: Is the 4656.275.018 interchangeable with aftermarket copies?
A: Only genuine ZF parts guarantee correct material hardness and dimensional accuracy. Aftermarket versions often fail prematurely due to inferior aluminum alloys and lack of hard anodizing, leading to contamination of the SCREEN SHEET filters.