Oil Pump Cleaning And Inspection

WARNING: This page is about a different car, the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, and 2018 Chevrolet Suburban. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: View Of Transfer Case Oil Pump Assembly & Suction Pipe

Courtesy of GENERAL MOTORS COMPANY

Callout	Component Name
Preliminary Procedure Inspect all components or sub-components and perform any repair procedure necessary to fix the damage. If the damage cannot be repaired, replace the component or sub-component as indicated. Clean all components in cleaning solvent and air dry.
1	Transfer Case Oil Pump Assembly NOTE: Replace the oil pump assembly if end play is evident or if there is any sign of binding. End play can be measured by inserting a feeler gauge between the outer rotor and housing. If the end play is greater than 0.1 mm (0.004 in), replace the oil pump assembly. Do not disassemble the oil pump. The oil pump is serviced as an assembly.
2	Transfer Case Oil Pump Suction Pipe NOTE: Replace the oil pump suction pipe if the screen is embedded with debris.

Callout

Component Name

Preliminary Procedure

Inspect all components or sub-components and perform any repair procedure necessary to fix the damage. If the damage cannot be repaired, replace the component or sub-component as indicated.
Clean all components in cleaning solvent and air dry.

Transfer Case Oil Pump Assembly

NOTE: Replace the oil pump assembly if end play is evident or if there is any sign of binding. End play can be measured by inserting a feeler gauge between the outer rotor and housing. If the end play is greater than 0.1 mm (0.004 in), replace the oil pump assembly. Do not disassemble the oil pump. The oil pump is serviced as an assembly.

Transfer Case Oil Pump Suction Pipe

NOTE: Replace the oil pump suction pipe if the screen is embedded with debris.