MercuryGrand Marquis2008Overview/mercury/grand-marquis/2008/base/

2008 Mercury Grand Marquis

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2008 Grand Marquis.

Body PASSENGER CARTransmission Automatic 4-spd

The 2008 Mercury Grand Marquis is a passenger car that calls for 6.0 qt of 5W‑20 API‑certified engine oil and is equipped with a four‑speed automatic transmission, returning EPA‑rated fuel economy of 15/23/18 mpg. It logged 78 total owner complaints for the model year, with steering noted as the top problem area and three recalls issued, placing it well below the 2005 peak of 487 complaints but above the 2011 low of nine. Consequently, the 2008 model year sits in the improved‑reliability portion of the Grand Marquis’s 1990‑2011 history, reflecting fewer issues than earlier years while not yet reaching the lowest complaint levels seen at the end of the run.

Model year201120102009200820072006200520042003

Quick specs

Fluid capacities, tune-up values and fuel economy at a glance.

Engine oil capacity6.0 qtOEM · verified
Engine oil type5W-20 APIOEM · verified
Lug nut torque100 ft-lbsOEM · verified
EPA fuel economy15/23/18 mpgEPA · verified

Fitment & sizes

Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.

Tire sizeP225-60R16OEM · verified

Full specifications

Engine, drivetrain, dimensions and economy.

Engine & drivetrain NHTSA vPIC

TransmissionAutomatic 4-spd

Ratings & economy EPA / vPIC

EPA city / highway / combined15 / 23 / 18 mpg
DrivetrainRear-Wheel Drive
Passenger volume107 cu ft
Cargo volume21 cu ft
Recommended fuelRegular Gasoline

Service quick specs OEM factory data

Capacities, torques and tune-up values from the factory service manual.

This engine holds 6.0 qt of 5W-20 API engine oil, DOT 3 brake fluid. Torque lug nuts to 100 ft-lbs, the oil drain plug to 19.0 ft-lbs. The firing order is 1-3-7-2-6-5-4-8. Note the cylinder-head bolts finish on a torque angle (torque-to-yield) — they stretch permanently and should be replaced, not reused, during any head service.

Lubricants & capacities

Automatic Transmission FluidATF
Automatic Transmission Fluid Capacity13.9
Brake FluidDOT 3
Engine CoolantUSE FORD PREMIUM GOLD COOLANT
Engine Oil5W-20 · API
Engine Oil Capacity6.0 qt
Power Steering FluidATF

Engine torques

Camshaft Bearing/Carrier Cap Bolts or Studs7.4 ft-lbs
Camshaft Bearing/Carrier Cap Bolts or Studs7.4 ft-lbs
Engine Flywheel Bolts59 ft-lbs
Engine Flywheel Bolts60-64 ft-lbs
Intake Manifold to Engine Bolts18 ft-lbs
Engine Oil Pan Drain Plug19.0 ft-lbs
Engine Oil Pan Drain Plug19.0 ft-lbs
Oil Pump to Cylinder BLock Bolts/Studs7 ft-lbs

Chassis torques

Lug Nuts100 ft-lbs

Ignition

Cylinder Firing Order1-3-7-2-6-5-4-8
Spark Plug ManufacturerMotorcraft
Spark Plug Gap0.052-0.056 in
Spark Plug Torque13.0 ft-lbs
Ignition Timing10

Battery & A/C

RefrigerantR134a
Refrigerant Capacity1.70 lbs
Oil GroupPAG
Oil Type46
Oil Capacity7.00 oz
Optional BCI Group Number65
Optional BCI Cranking Performance650 cca

Service checks

Pressure Test16 psi
Radiator Cap Pressure Relief16 psi
Thermostat Opening Temperature188-195 °F
Key ON Engine OFF (KOEO)20.0-60.0
Injector Primary Resistance11-18 ohms
Engine Oil Pressure20-45 psi
Engine Oil Pressure RPM2500 rpm
Engine Oil Pressure40-70 psi

Brakes

Torque Caliper to Bracket18 ft-lbs / 27 ft-lbs
Torque to Knuckle50 ft-lbs / 118 ft-lbs
Minimum Pad ThicknessFront: 0.118; Rear: 0.118 in
Minimum Pad ThicknessFront: 0.118; Rear: 0.118 in
Rotor Runout Limit0.002 in
Rotor Minimum Machining0.732 in / 1.061 in
Rotor Discard at or Under0.708 in / 1.037 in

Multi-step torque procedures OEM · verified

Connecting Rod (Large End) Bearings — tightening sequence 1 stages
118 ft. lbs., Step 2: 33 ft. lbs. Step 3: 9018 ft. lbs
Connecting Rod (Large End) Bearings — tightening sequence 1 stages
117 ft. lbs., Step 2: 32 ft. lbs., Step 3: 10517 ft. lbs
Crankshaft Pulley and/or Damper Bolts — tightening sequence 1 stages
166 ft. lbs., step 2: 360 degrees, step 3: 37 ft. lbs., step 4: 9066 ft. lbs
Cylinder Head — tightening sequence 6 stages
130 ft. lbs.30 ft. lbs
290 degrees90 degrees
3loosen 1 turn
430 ft. lbs.30 ft. lbs
590 degrees90 degrees
690 degrees90 degrees
Exhaust Manifold to Cylinder Head Bolts — tightening sequence 1 stages
1install 8 new exhaust manifold stud9 ft. lbs

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the engine oil and filter every 7,500 mi; coolant every 50,000 mi. The big-interval services (every 50,000 mi for coolant, and the transmission fluid) are the ones owners most often skip — on a lower-mileage example, assume the original fluids are still in it and check them first.

Every 7,500 miEngine Oil (drain & refill) · Engine Oil Filter (replace) · Tire & Wheel Assembly (rotate)
Every 15,000 miBrake System (inspect) · Cabin Air Filter (replace) · Engine Coolant System Hoses (inspect) · Steering Linkage (inspect) · Transmission Assembly (inspect fluid level) · Wheel Bearing (inspect)
Every 30,000 miEngine Air Filter Element (replace) · Exhaust System (Complete) (inspect) · Fuel Filter (replace) · Temperature Controlled Seat Air Filter (replace)
Every 50,000 miEngine Coolant System (drain, flush & refill)
At 100,000 miEngine Coolant System (drain, flush & refill)
Every 100,000 miAccessory Drive Belt (inspect) · Drive Axle Assembly (drain & refill) · PCV Valve (replace)
At 150,000 miDrive Belt (replace) · Transmission Fluid & Filter (replace)

Reliability & federal safety record

Owner-reported issues, recalls, investigations and service bulletins on record with NHTSA — an unfiltered look at what owners actually experience.

The 2008 Mercury Grand Marquis recorded 78 federal complaints, three recalls and one investigation, with a total of 16 TSBs. Compared to the preceding 2007 model year (96 complaints, two investigations, 17 TSBs) and the following 2009 model year (26 complaints, two recalls, zero investigations, 16 TSBs), 2008 sits in the middle of a steep decline that began after 2005. Its top complaint categories were steering (17 complaints), vehicle speed control (10), structure (6) and electrical system (5), while crash‑related and fire complaints were limited to 11 and 1 respectively. The complaint trajectory shows a clear downward trend across the generation, positioning 2008 near the tail end of higher‑volume years but still above the very low levels seen in 2009 onward. Consequently, the 2008 model year offers a reasonable balance of lower overall complaints and stable recall activity, making it a defensible used‑car purchase provided a thorough inspection of steering components is performed.

3
Open recalls
NHTSA campaigns
16
Service bulletins
Manufacturer communications
1
ODI investigations
Office of Defects Investigation
78
Owner complaints
11 involved a crash · 1 a fire
Owner complaints by model year NHTSA · this generation & adjacent

Owner complaints filed with NHTSA, by component

All 78 complaints on record, top 8 components.

Steering17
Vehicle Speed Control10
Structure6
Electrical System5
Service Brakes, Hydraulic4
Exterior Lighting2
Seat Belts2
Fuel System, Gasoline2

Source: NHTSA Office of Defects Investigation complaint database.

Recalls NHTSA · verified

Showing 2 of 3 campaigns on record for this vehicle.

14V704000Steering:Rack And Pinion:Pinion ShaftReported 05/11/2014

Ford Motor Company (Ford) is recalling certain model year 2005-2011 Ford Crown Victoria, 2005-2011 Mercury Grand Marquis vehicles manufactured March 23, 2004, to August 30, 2011, and 2005-2011 Lincoln Town Car vehicles… Remedy: Ford will notify the owners of vehicles whose repair records reflect that the upper intermediate steering shaft was repaired during the course of the prior recall 13V-385. Dealers…

13V385000SteeringReported 29/08/2013

Ford is recalling certain model year 2005-2011 Ford Crown Victoria (including Crown Victoria Police Interceptors), Mercury Grand Marquis, and Lincoln Town Car vehicles. The affected vehicles are currently registered or… Remedy: Ford will notify owners and dealers will replace the lower intermediate shaft, free of charge. The upper intermediate shaft and steering column lower bearing will be inspected to…

Technical service bulletins NHTSA · verified

Showing 5 of 16 bulletins on record with NHTSA.

BulletinDateComponentSummary
DOR-L2Q6V-102019-09-18Electrical SystemThis SKU is a Radiator Fan. The customer communication requested return of unsold…
SSM 472012018-03-30EquipmentReplacing the original equipment SYNC/Navigation system with either an aftermarket…
SSM 463322017-01-24EquipmentREPLACING THE ORIGINAL EQUIPMENT SYNC/NAVIGATION SYSTEM WITH EITHER AN AFTERMARKET…
SSM 460852016-09-21Engine And Engine CoolingThe Powertrain Control/Emissions Diagnosis (PC/ED) manual has been revised for diagnosing…
TSB1600722016-04-21StructureInpected or repaired under 13R01 - Requests for recall service action under 13S08

Common OBD-II trouble codes

The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.

P0420
Catalyst system efficiency below threshold — Bank 1
P0300
Random / multiple cylinder misfire detected
P0171
System too lean — Bank 1
P0455
Evaporative emission system leak detected — large leak
P0128
Coolant thermostat below regulating temperature
P0442
Evaporative emission system leak detected — small leak

VIN tools

Decode factory build data for a specific vehicle by VIN.

VIN
Decode a VIN to confirm the transmission and build data for a specific Grand Marquis. OEM
Build data
Plant, GVWR class, engine and body data for any 17-character VIN.
Recalls
Check open recall campaigns against a specific vehicle by VIN.

Vehicles with shared specs

Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.

Reference guides

Cross-vehicle references for the kinds of data on this page.

Frequently asked

How much oil does the 2008 Grand Marquis take?

6.0 qt of 5W-20 API MEETING FORD SPECIFICATION WSS-M2C945-A, per the factory manual.

Does the 2008 Grand Marquis have open recalls?

NHTSA lists 3 recall campaign(s) for this model year. Check your specific vehicle by VIN.

What gas mileage does the Grand Marquis get?

EPA figures are 15 city / 23 highway / 18 combined mpg.