AUTOMATIC TRANSMISSION SERVICE GROUP
Technical ServiceInformation
6
Copyright © 2003 ATSG
PTO "GENERAL" REQUIREMENTS:
RFF81P-7006-BA
Ford
FordFord
98
XW4P-AC
RJL-B
004361
BD-9C17
PTO
Window
Figure 5
(1)Obviously the case must be PTO capable with
the cast-in window in the transmission where the
PTOunitmountstothetransmission,asshownin
Figure5.
(2)Designed for use during Mobile (Some Models)
orStationaryconditions.
Shift Solenoid 2 and the Coast Clutch Solenoid
mustbeenergizedwhenthePTOisturnedON.
(3)PTOisavailableasanoptiononlyon 8500GVW
or above, Super Duty F-Series trucks with 6.8L
Gasoline and 7.3L Diesel engines. Ford 4R100
transmissions on other models are not PTO
capable.
(4)
(5)
Battery voltage must be supplied to the
Powertrain Control Module (PCM) input pin 4
on gasoline models, or pin 66 on diesel models,
when the PTO is engaged. The processor uses
this information to raise EPC pressure to
approximately 55 PSI so that you do not burn the
coast clutch. This voltage must be provided by
thePTOinstaller.
"GENERAL" CONDITIONS FOR OPERATION
(1)
(2)
(3)
(4)
(5)
Thevehicleisnotinthecrankorstartmode.
The transmission range selector must be in the P,
R,O.D,2or1position. ThePTOwillnotoperate
whenselectorisintheneutralposition.
PTO operation is inhibited when in cranking
mode,neutral,or4thgear.
Transmission only operates 1st through 3rd
gears. Computer strategy does not allow 4th
geartoengage,underanyconditions.
Transmission Fluid Temperature Sensor (TFT)
readingmustbeuptooperatingtemperature.
Specific Operation For Diesel, See Page 7.
GASOLINE ENGINE PTO OPERATION:
(1)
(2)
(3)
(4)
PTO installer must obtain a "High Idle Throttle
Control"fromanaftermarketsource.
Auxiliary Powertrain Control Module seen on
Pageseven,doesnotworkonthegasolineengine
models. APCM module works only on the 7.3L
dieselengine.
For stationary PTO operation an engine idle
speedof1300RPMisrequired.
The Torque Converter Clutch (TCC) engages
oncetheenginereaches1300RPM.
TRANSMISSION FUNCTIONS
DURING PTO OPERATION:
(1)
(2)
(3)
(4)
(6)
(5)
Shift Solenoid 2 and Coast Clutch Solenoids are
turned on, the coast clutch activates and does not
allow4thgearoperationduringPTOoperation.
Electronic Pressure Control (EPC) pressure is
raised to approximately 55 PSI. This is why the
coast clutch will be smoked in a short period of
time if a battery voltage wire is not supplied to
EEC input pin 4 (gasoline) or pin 66 (diesel)
when the PTO is engaged, as this rise in pressure
wouldnotoccur.
The Transmission Control Indicator Lamp
(TCIL)illuminates.
When the PTO is turned ON, the transmission
operates only in 1st through 3rd gears.
Overdrive 4th gear is not allowed by the PCM
strategy.
PTO operation can cause transmission fluid
temperature to exceed the recommended
maximum limit of 250 degrees F. Failure mode
logicwithin PCMstrategypreventstransmission
damage by disabling the PTO above this
temperaturelimit.
The transmission shift schedule is earlyand shift
feelisveryfirm.
