Overview
The Omix-ADA NP231/NP242 oil pump housing, part number 18676.47, is a replacement oil pump housing for the NP231 and NP242 transfer cases. It fits the 1987 to 1995 Jeep Wrangler YJ and the 1997 to 2001 Jeep Wrangler TJ.
Fitment covers the trims named in the fitment section below, so compare your trim before buying.
Key features
- Replacement housing made to OE specifications
- Made for the NP231 and NP242 transfer cases
- Wrangler YJ coverage from 1987 to 1995
- Wrangler TJ coverage from 1997 to 2001
Transfer case work basics
The oil pump in a transfer case circulates lubricant to the gears and bearings, so a housing that leaks or cracks can lead to low fluid and bearing wear. Because the housing sits inside the case, replacement usually means draining the fluid, removing the case cover, and cleaning the mating surfaces thoroughly.
Use a new gasket set and inspect the pump gears and the drive chain while the case is open. Fill with the lubricant named in your service manual and check the level once the case is back together.
Signs of trouble include fluid seepage at the case, whining from the transfer case, or metal in drained fluid. Check the fluid level and condition regularly, especially after off-road use, and address leaks before they reach the bearings.
- Fluid seeping from the case
- Whining from the transfer case
- Metal debris in drained fluid
- Low fluid after a leak
Specifications
| Brand | Omix-ADA |
|---|---|
| Part number | 18676.47 |
| UPC | 804314029364 |
| Type | Oil pump housing |
| Transfer case | NP231/NP242 |
Vehicle fitment
It fits these vehicles:
- 1997 to 2001 Jeep Wrangler (TJ), SE, Sahara and Sport trims
- 1987 to 1995 Jeep Wrangler (YJ), Base, Islander, Laredo, Renegade, Rio Grande, S, SE, Sahara and Sport trims
Wrangler TJ years from 2002 to 2006 are not on the list, and Cherokee and Grand Cherokee models are not covered. Confirm your vehicle’s year, model and trim before ordering.
Installation notes
The housing is part of the NP231/NP242 transfer case, so replacing it means opening the case. Plan for that work and follow the transfer case service procedure for your model.
What’s included
The housing is the only item named. Check the gaskets, seals and fasteners against your installation for the job before you start.
