How to Properly Maintain the Oil Pressure Switch in a Mercury Grand Marquis?

Start the service of the oil pressure switch by placing the vehicle on a hoist with NEUTRAL transmission. Begin by disconnecting the ground cable of the battery before unplugging the electrical wire from the oil pressure switch along with switch removal. Tighten the new switch to 14 Nm (10 ft. lbs.) after which perform an additional 180-degree tightening. You should complete the installation by performing the reverse steps of removal.

How to Service the Oil Pressure Switch on Mercury Mariner?

Service of the oil pressure switch starts with positioning the vehicle on a hoist and setting it to NEUTRAL. The right-hand splash shield requires five bolts to be removed before installation when tightening them to 9 Nm (80 inch lbs.) during reinstallation. First detach the electrical connector from the oil pressure switch before removing the switch from its location while tightening the installation to 15 Nm (11 ft. lbs.). Completely reverse the uninstallation steps before applying Teflon-containing pipe sealant to the oil pressure switch threads.

How to Service the Oil Pressure Switch on Mercury Cougar?

The first step for servicing an oil pressure switch requires the battery ground cable to be disconnected. Afterwards, the vehicle needs to be supported by a suitable lift before several more steps. The first step includes disconnecting the electrical connector from the oil pressure switch before removing the oil pressure switch. Follow the opposite steps of the removal process to install the device.

OEM Mercury Oil Pressure Switch

Oil Pressure Sender Switch

Select Vehicle by Model
Select Vehicle by VIN

Select Vehicle by Model

Make

Model

Year

Select Vehicle by VIN

For the most accurate results, select vehicle by your VIN (Vehicle Identification Number).

17 Oil Pressure Switches found

View related parts
Mercury Oil Pressure Sensor
Part Number: GC3Z-9278-B
$20.37 MSRP: $31.53
You Save: $11.16 (36%)
Ships in 1 Business Day
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Gauge Sw; Pressure Switch; Oil Pressure Switch; Pressure Sensor; Sending Unit; Switch Assembly; Oil Gauge
- Replaces: 6U5Z-9278-D, 1U5Z-9278-DA, GC3Z-9278-A, SW-6357
Fits the following Mercury Models:
- Grand Marquis | 2000-2011 | GS, GSL, Limited Edition, LS, LSE, Ultimate Edition | 8 Cyl 4.6 L FLEX, 8 Cyl 4.6 L GAS
- Marauder | 2003-2004 | Base | 8 Cyl 4.6 L GAS
- Mountaineer | 1999-2010 | Base, Convenience, Luxury, Premier | 6 Cyl 4.0 L GAS, 8 Cyl 4.6 L GAS, 8 Cyl 5.0 L GAS
- Sable | 2008-2009 | Base, Premier | 6 Cyl 3.5 L GAS
View More
View related parts
Mercury Pressure Switch, Green
Part Number: BE8Z-9278-A
$2.27 MSRP: $3.60
You Save: $1.33 (37%)
Ships in 1 Business Day
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Sending Unit; Switch; Oil Pressure Switch
- Replaces: 1S7Z-9278-AA, SW-6682
Fits the following Mercury Models:
- Mariner | 2005-2008 | Base, Convenience, Hybrid | 4 Cyl 2.3 L FULL HYBRID EV-GAS (FHEV), 4 Cyl 2.3 L GAS
View related parts
Mercury Pressure Switch
Part Number: G1CZ-9278-B
$24.30 MSRP: $38.58
You Save: $14.28 (38%)
Ships in 1 Business Day
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Sending Unit; Oil Pressure Switch
- Replaces: 1U5Z-9278-GA, SW-6376, 6U5Z-9278-G, G1CZ-9278-A
Fits the following Mercury Models:
- Mariner | 2009-2011 | Base, Hybrid, Premier | 4 Cyl 2.5 L FULL HYBRID EV-GAS (FHEV), 4 Cyl 2.5 L GAS
- Milan | 2006-2011 | Base, Hybrid, Premier | 4 Cyl 2.3 L GAS, 4 Cyl 2.5 L FULL HYBRID EV-GAS (FHEV), 4 Cyl 2.5 L GAS
View related parts
Mercury Oil Pressure Sending Unit
Part Number: D4AZ-9278-A
$45.08 MSRP: $72.73
You Save: $27.65 (39%)
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Gauge Sw; Oil Pressure Switch; Oil Gauge; Oil Gauge Sending Unit
Fits the following Mercury Models:
- Colony Park | 1987-1991 | GS, LS | 8 Cyl 5.0 L GAS
- Cougar | 1984-1997 | Base, LS, XR-7 | 4 Cyl 2.3 L GAS, 6 Cyl 3.8 L GAS, 8 Cyl 4.6 L GAS, 8 Cyl 5.0 L GAS
- Grand Marquis | 1984-1991 | Base, Colony Park, GS, LS | 8 Cyl 5.0 L GAS
- Lynx | 1984-1987 | Base, GL, GS, L, LS, LTS, RS, XR3 | 4 Cyl 1.6 L GAS, 4 Cyl 1.9 L GAS
- Marquis | 1984-1986 | Base, Brougham | 4 Cyl 2.3 L GAS, 4 Cyl 2.3 L LPG, 6 Cyl 3.8 L GAS
- Mountaineer | 1997-1998 | Base | 6 Cyl 4.0 L GAS, 8 Cyl 5.0 L GAS
- Mystique | 1995-2000 | Base, GS, GS Spree, LS, LS Young America | 6 Cyl 2.5 L GAS
- Sable | 1986-1995 | GS, LS, LTS | 4 Cyl 2.5 L GAS, 6 Cyl 3.0 L GAS, 6 Cyl 3.8 L GAS
- Topaz | 1984-1994 | Base, GS, GS AWD, LS, LS AWD, LTS, LTS AWD, Sport, Sport AWD, XR5, XR5 AWD | 4 Cyl 2.3 L GAS, 6 Cyl 3.0 L GAS
- Tracer | 1991-1999 | Base, GS, LS, Trio | 4 Cyl 1.9 L GAS, 4 Cyl 2.0 L GAS
View More
View related parts
Mercury Oil Pressure Switch
Part Number: E4ZZ-9278-A
$21.07 MSRP: $33.45
You Save: $12.38 (38%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Sender Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Gauge Sw; Oil Pressure Sending Unit
Fits the following Mercury Models:
- Cougar | 1984-1988 | Base, LS, XR-7 | 4 Cyl 2.3 L GAS, 6 Cyl 3.8 L GAS, 8 Cyl 5.0 L GAS
- Marquis | 1984-1986 | Base, Brougham | 4 Cyl 2.3 L GAS, 4 Cyl 2.3 L LPG, 6 Cyl 3.8 L GAS
View related parts
Mercury Oil Pressure Sending Unit
Part Number: F5RZ-9278-A
$7.94 MSRP: $10.80
You Save: $2.86 (27%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Gauge Sending Unit
Fits the following Mercury Models:
- Mystique | 1995-1999 | Base, GS, GS Spree, LS | 4 Cyl 2.0 L GAS
- Sable | 1996 | G, GS, LS | 6 Cyl 3.0 L GAS
- Tracer | 1998-1999 | GS, LS, Trio | 4 Cyl 2.0 L GAS
View More
View related parts
Mercury Oil Pressure Sending Unit
Part Number: XS2Z-9278-AA
$2.05 MSRP: $3.31
You Save: $1.26 (39%)
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch
- Replaces: XS2Z-9278-CA
Fits the following Mercury Models:
- Cougar | 1999-2002 | Base | 4 Cyl 2.0 L GAS
View related parts
Mercury Pressure Switch
Part Number: 6U5Z-9278-M
$102.89 MSRP: $172.73
You Save: $69.84 (41%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Gauge Sw; Oil Pressure Switch; Oil Pressure Sending Unit; Oil Gauge Sending Unit
- Manufacturer Note: 3/8" NPTF
- Replaces: 1U5Z-9278-BA, 6U5Z-9278-L, SW-6362
Fits the following Mercury Models:
- Cougar | 1999-2002 | Base, S, V6 | 6 Cyl 2.5 L GAS
- Mariner | 2005-2008 | Base, Premier | 6 Cyl 3.0 L GAS
- Montego | 2005-2007 | Luxury, Premier | 6 Cyl 3.0 L GAS
- Sable | 1999-2005 | GS, LS, LS Premium, Platinum Edition | 6 Cyl 3.0 L GAS
View More
View related parts
Mercury Pressure Switch
Part Number: 6U5Z-9278-A
$124.20 MSRP: $209.09
You Save: $84.89 (41%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Oil Pressure Switch; Oil Pressure Sending Unit; Oil Gauge Sending Unit
- Replaces: 1U5Z-9278-AA, F8AZ-9278-AA
Fits the following Mercury Models:
- Sable | 1999-2005 | GS, LS, LS Premium, Platinum Edition | 6 Cyl 3.0 L GAS
View related parts
Mercury Oil Pressure Sending Unit
Part Number: F3XY-9278-B
$24.37 MSRP: $33.16
You Save: $8.79 (27%)
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Light Sw
- Manufacturer Note: #25240,89920
Fits the following Mercury Models:
- Villager | 1993-2002 | Base, Estate, GS, LS, Nautica, Sport | 6 Cyl 3.0 L GAS, 6 Cyl 3.3 L GAS
View related parts
Mercury Oil Pressure Sending Unit
Part Number: E9BZ-9278-A
$19.43 MSRP: $26.44
You Save: $7.01 (27%)
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch
Fits the following Mercury Models:
- Tracer | 1991 | LTS | 4 Cyl 1.8 L GAS
View related parts
Mercury Oil Pressure Sending Unit
Part Number: XS2Z-9278-CA
$2.08 MSRP: $3.31
You Save: $1.23 (38%)
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch
- Replaced by: XS2Z-9278-AA
Fits the following Mercury Models:
- Mystique | 2000 | GS | 4 Cyl 2.0 L GAS
View related parts
Mercury Pressure Switch
Part Number: 6U5Z-9278-N
$127.08 MSRP: $209.09
You Save: $82.01 (40%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Sending Unit; Oil Pressure Switch
- Replaces: SW-6356, 6U5Z-9278-J
Fits the following Mercury Models:
- Mariner | 2008-2011 | Base, Premier | 6 Cyl 3.0 L FLEX, 6 Cyl 3.0 L GAS
- Milan | 2006-2011 | Base, Premier | 6 Cyl 3.0 L FLEX, 6 Cyl 3.0 L GAS
View related parts
Mercury Oil Pressure Sending Unit
Part Number: D2AZ-9278-AA
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Gauge Sw; Oil Gauge Sending Unit
Fits the following Mercury Models:
- Cougar | 1999 | V6 | 6 Cyl 2.5 L GAS
- Sable | 1996-1998 | G, GS, LS, LS Premium | 6 Cyl 3.0 L GAS
View related parts
Mercury Oil Pressure Switch
Part Number: E9SZ-9278-A
$12.22 MSRP: $18.91
You Save: $6.69 (36%)
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch; Oil Pressure Gauge Sw; Oil Pressure Sending Unit; Oil Gauge Sending Unit
- Replaces: F4TZ-9278-A
Fits the following Mercury Models:
- Cougar | 1989-1997 | LS, XR-7 | 6 Cyl 3.8 L GAS, 8 Cyl 4.6 L GAS
- Grand Marquis | 1992-1999 | GS, LS | 8 Cyl 4.6 L GAS
- Mountaineer | 1997-1998 | Base | 6 Cyl 4.0 L GAS, 8 Cyl 5.0 L GAS
View More
View related parts
Mercury Belt Tensioner
Part Number: E9ZZ-9278-A
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Serpentine Belt Drive Kit; Oil Pressure Sending Unit; Serpentine Tensioner
Fits the following Mercury Models:
- Capri | 1985-1986 | 5.0, RS | 8 Cyl 5.0 L GAS
View related parts
Mercury Oil Pressure Sending Unit
Part Number: 6U5Z-9278-K
Product Specifications
- Other Name: Switch Assembly - Oil Pressure; Engine Oil Pressure Switch
- Replaces: 1U5Z-9278-FA
Fits the following Mercury Models:
- Monterey | 2004-2007 | Base, Convenience, Luxury, Premier | 6 Cyl 4.2 L GAS

Mercury Oil Pressure Switch Parts Questions & Experts Answers

Oil Pressure Sensor
GC3Z-9278-B
Q: How to Properly Maintain the Oil Pressure Switch in a Mercury Grand Marquis?
A: Start the service of the oil pressure switch by placing the vehicle on a hoist with NEUTRAL transmission. Begin by disconnecting the ground cable of the battery before unplugging the electrical wire from the oil pressure switch along with switch removal. Tighten the new switch to 14 Nm (10 ft. lbs.) after which perform an additional 180-degree tightening. You should complete the installation by performing the reverse steps of removal.
Pressure Switch
6U5Z-9278-M
Q: How to Service the Oil Pressure Switch on Mercury Mariner?
A: Service of the oil pressure switch starts with positioning the vehicle on a hoist and setting it to NEUTRAL. The right-hand splash shield requires five bolts to be removed before installation when tightening them to 9 Nm (80 inch lbs.) during reinstallation. First detach the electrical connector from the oil pressure switch before removing the switch from its location while tightening the installation to 15 Nm (11 ft. lbs.). Completely reverse the uninstallation steps before applying Teflon-containing pipe sealant to the oil pressure switch threads.
Oil Pressure Sending Unit
XS2Z-9278-AA
Q: How to Service the Oil Pressure Switch on Mercury Cougar?
A: The first step for servicing an oil pressure switch requires the battery ground cable to be disconnected. Afterwards, the vehicle needs to be supported by a suitable lift before several more steps. The first step includes disconnecting the electrical connector from the oil pressure switch before removing the oil pressure switch. Follow the opposite steps of the removal process to install the device.