2008 FORD F350 octane

Octane recommendations
Your vehicle is designed to use
“Regular” unleaded gasoline with
pump (R+M)/2 octane rating of 87.
We do not recommend the use of
gasolines labeled as “Regular” that
are sold with octane ratings of 86 or lower in high altitude areas.
Do not be concerned if your engine sometimes knocks lightly. However, if
it knocks heavily under most driving conditions while you are using fuel
with the recommended octane rating, see your authorized dealer to
prevent any engine damage.
Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems, try a different brand of unleaded gasoline. “Premium”
unleaded gasoline is not recommended for vehicles designed to use
“Regular” unleaded gasoline because it may cause these problems to
become more pronounced. If the problems persist, see your authorized
dealer.
Do not add aftermarket fuel additive products to your fuel tank. It
should not be necessary to add any aftermarket products to your fuel
tank if you continue to use high quality fuel of the recommended octane
rating. These products have not been approved for your engine and
could cause damage to the fuel system. Repairs to correct the effects of
using an aftermarket product in your fuel may not be covered by your
warranty.
Many of the world’s automakers approved the World-wide Fuel Charter
that recommends gasoline specifications to provide improved
performance and emission control system protection for your vehicle.
Gasolines that meet the World-wide Fuel Charter should be used when
available. Ask your fuel supplier about gasolines that meet the
World-wide Fuel Charter.
Cleaner air
Ford endorses the use of reformulated “cleaner-burning” gasolines to
improve air quality, per the fuel recommendations in theChoosing the
right fuelsection.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
affect on powertrain components.
87(R+M)/2 METHOD
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
366
ProCarManuals.com

•Use the same filling rate setting (low-medium-high) each time the
tank is filled.
•Allow no more than 2 automatic click-offs when filling.
•Always use fuel with the recommended octane rating.
•Use a known quality gasoline, preferably a national brand.
•Use the same side of the same pump and have the vehicle facing the
same direction each time you fill up.
•Have the vehicle loading and distribution the same every time.
Your results will be most accurate if your filling method is consistent.
Calculating fuel economy
1. Fill the fuel tank completely and record the initial odometer reading
(in miles or kilometers).
2. Each time you fill the tank, record the amount of fuel added (in
gallons or liters).
3. After at least three to five tank fill-ups, fill the fuel tank and record
the current odometer reading.
4. Subtract your initial odometer reading from the current odometer
reading.
5. Follow one of the simple calculations in order to determine fuel
economy:
Calculation 1:Divide total miles traveled by total gallons used.
Calculation 2:Multiply liters used by 100, then divide by total
kilometers traveled.
Keep a record for at least one month and record the type of driving (city
or highway). This will provide an accurate estimate of the vehicle’s fuel
economy under current driving conditions. Additionally, keeping records
during summer and winter will show how temperature impacts fuel
economy. In general, lower temperatures give lower fuel economy.
Driving style - good driving and fuel economy habits
Give consideration to the lists that follow and you may be able to change
a number of variables and improve your fuel economy.
Habits
•Smooth, moderate operation can yield up to 10% savings in fuel.
•Steady speeds without stopping will usually give the best fuel
economy.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
368
ProCarManuals.com

ENGINE DATA
Engine 5.4L V8 engine 6.8L V10 engine
Cubic inches 330 415
Required fuel 87 octane 87 octane
Firing order 1-3-7-2-6-5-4-8 1-6-5-10-2-7-3-8-4-9
Spark plug gap1.02–1.28mm
(0.040–0.050 inch)*1.02–1.28mm
(0.040–0.050 inch)*
Ignition system Coil on plug Coil on plug
Compression ratio 9.8:1 9.2:1
*The 5.4L 3V and 6.8L 3V spark plug gap CANNOT be adjusted.
Drivebelt routing
5.4L V8/6.8L V10 engines
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
387
ProCarManuals.com

Family entertainment system ....48
Fluid capacities .........................383
Foglamps .....................................85
Four-Wheel Drive vehicles .......276
description ..............................281
driving off road .......................283
electronic shift ................277, 281
indicator light .........................278
lever operated shift ................278
manual locking hubs ..............277
preparing to drive your
vehicle .....................................264
Fuel ............................................362
calculating fuel
economy ..........................130, 367
cap ...........................................364
capacity ...................................383
choosing the right fuel ...........365
comparisons with EPA fuel
economy estimates .................370
detergent in fuel .....................366
filling your vehicle with
fuel ...........................362, 364, 367
filter, specifications ........362, 382
fuel pump shut-off switch .....296
improving fuel economy ........367
octane rating ...................366, 387
quality ......................................366
running out of fuel .................366
safety information relating to
automotive fuels .....................362
Fuel pump shut-off switch .......296
Fuses ..................................297–298
G
Gas cap (see Fuel cap) ............364
Gas mileage
(see Fuel economy) .................367
Gauges .........................................19transmission fluid
temperature gauge ...................23
H
Hazard flashers .........................296
Head restraints .........................162
Headlamps ...................................85
aiming ..................................87, 89
autolamp system .......................85
daytime running lights .............86
flash to pass ..............................86
high beam .................................86
replacing bulbs ...................93–94
turning on and off ....................85
Heating
heating and air conditioning
system ...........................76–77, 80
Homelink wireless control
system ........................................116
Hood ..........................................347
I
Ignition ...............................255, 387
Infant seats
(see Safety seats) .....................196
Inspection/maintenance (I/M)
testing ........................................372
Instrument panel
cleaning ...........................340–341
cluster ........................................12
lighting up panel and interior .87
J
Jump-starting your vehicle ......322
K
Keyless entry system ...............157
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Index
394
ProCarManuals.com

autolock ...................................147
programming entry code .......157
Keys ...........................................160
positions of the ignition .........255
L
Lamps
autolamp system .......................85
daytime running light ...............86
fog lamps ...................................85
headlamps .................................85
headlamps, flash to pass ..........86
instrument panel, dimming .....87
interior lamps ...........................91
replacing bulbs .............91, 93–97
Lane change indicator
(see Turn signal) ........................90
Lights, warning and indicator ....12
anti-lock brakes (ABS) ..........261
Load limits .................................236
Loading instructions .................242
Locks
autolock ...................................147
childproof ................................150
Lug nuts ....................................321
Lumbar support, seats .............167
M
Manual transmission .................269
fluid capacities ........................383
reverse .....................................271
Message center .................120, 129
english/metric button .............132
system check button ..............132
warning messages ...........124, 135
Mirrors ...............................100, 103
fold away .........................105, 107heated ......................................105
side view mirrors (power) .....104
signal .......................................108
Moon roof ..................................115
Motorcraft parts ................362, 382
N
Navigation system .......................47
O
Octane rating ............................366
Oil (see Engine oil) ..................351
Overdrive .....................................99
P
Parking brake ............................261
Parts (see Motorcraft parts) ....382
Pedals (see Power adjustable
foot pedals) ...............................108
Power adjustable foot pedals ...108
Power distribution box
(see Fuses) ...............................303
Power door locks ......................146
Power mirrors ...........................104
Power point ...............................100
Power steering ..........................263
fluid, checking and adding ....373
fluid, refill capacity ................383
Power Windows .........................102
Preparing to drive your
vehicle ........................................264
R
Radio ................................23, 25, 32
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Index
395
ProCarManuals.com