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Ford 4R70W/4R75W Transmission
Ford introduced the
AOD transmission in full size passenger cars and
light duty trucks. This was a hydraulic
transmission with throttle cable and
1993: (half year,
Depending on month produced you could
have hydraulic or computer controlled
ford transmission) they introduced the
AODE which is the same
also brought us the 4R70W
Transmission which is the same
as an AODE Transmission
except for a lower 1st and 2nd gear
ratios as well as higher overdrive ratio
for fuel economy.
2003: Ford upgraded the 4R70W
transmission which has an
improved ring gear and pump assembly for
durability, and added VSS as well as
output sensor. They also modified
it again calling it the
4R75W/4R75E Transmission which
is basically the same as the
4R70W except has an input
sensor for the TCM to deal with
fly-by-wire throttle controls.
Technical information for Ford 4R70W and 4R75W Transmissions
including harness connector pin
identification and pressure testing
Complaint: 4R70W Torque converter shudder, feels like running over washboard
The Torque converter clutch shuddering on a 4R70W transmission is a common complaint and can be caused by
deteriorated fluid, sometimes simply changing the fluid and filter can
remedy this problem. You can check the
Bypass clutch control valve and sleeve
, there are replacements available
thru Sonnax. Be sure to use only MerconV fluid or you can create a shudder. If
you change the fluid and pan was clean and you still have shudders then may be
the stator bushings are worn badly and or the TCC clutch in the torque
Complaint: 4R70W transmission Neutrals out
During 3-4 upshift.
Cause: This can be caused by the 4th band servo snap ring has broken into small pieces and
worked its way thru the valve body and into the
Overdrive servo regulator valve
jamming the valve open, when this
transmission goes into 4th gear or overdrive the forward clutch releases and if
you have no servo apply due to jammed valve you end up with a neutral condition.
To repair this condition, remove valve body and replace front 4th servo snap
ring with new. make sure you get all the broken parts of snap ring out of the
valve, and all of valve body cavities. If you dont you can have a repeat of the
same of worse weve seen snap ring parts go into the pump and
destroy the gears
and converter hub. IMPORTANT
: you cannot let the servo
fall out of the case!
you will drop the band and have no 4th, this
cannot be fixed without removing the transmission and pump to reposition the
band! when you remove snap ring you need to hold servo in with screw jack or
fixture, there's a heavy spring under and it will fly out, if snap ring ends are
both broken off you can drill one broken end with small drill so you can use
pick etc to pry snap ring out.
If this is not found to be your problem you may have failed shift solenoid,
ripped servo seal, broken or wiped out 4th band or broken sun gear shell (which
will also give you no reverse)
Complaint: 4R70W transmission Neutrals out
After 3-4 upshift.
Cause: This was a common problem with earlier models with the shift solenoids
mechanically sticking or weak , will shift 3-4 and then neutral out, will
sometimes have to stop vehicle completely to to get forward movement back. If
vehicle simply neutrals out when it shifts see the bulletin above. remove pan
and if clean of debris you can change the shift solenoid assembly and remedy
Complaint: 4R70W no 2-3 upshift.
Cause: Most common cause here is the splines inside the direct drum have
stripped out due to wear. check the spline inside the drum that the small shaft
go into and replace drum as necc. good idea on any rebuild to install new drum
if any wear is found so it wont be back soon. If you get a 2-3 shift but slips
then your direct clutches are slipping, stripped splines will cause no 2-3
shift at all, will stay in 2nd gear all day.
Complaint: 4R70W locked up, severe noises, stalls engine
when put into gear, wont roll forwards or backwards when pushed.
Cause: The Torrington bearings like to wipe out and then get into the gear train
and cause catastrophic destruction of the planetary and rear section of the
trans, can cause engine stalling and you may not be able to even push the
vehicle forward or backwards and have to remove the drive shaft to roll. This is
due to the fact that this is a car transmission that's being overloaded in a
truck application and wipes out the bearings from the load. Replace all bearings
on any overhaul to prevent this from happening later. For some reason unknown to
mankind Ford has decided that they can put this transmission into an F-250 and
even and E-350 van, which will work, just for how long? it was designed for a
Crown-Victoria, not to tow your camper with an F-250 truck up mountains. If you
want to tow and work a ford truck make sure you get the heavy 250, not the light
duty version, you'll get a 4R100 up till 2004 and 5R110W after 2005. The van
seems another story as we said the E-350 can come with this 4R75W transmission.
Complaint: 2004 and up: Very slow speedometer and codes P0720 or P0722
VSS (After rebuild only).
Cause: After rebuild speedometer is reading very slow, gear set was replaced
during overhaul, In 2004 Ford changed the rear ring gear by extending the park
lugs to replace the holes the speed sensor used to read from. If during the
overhaul the ring gear was replaced with an earlier version you will have this
problem. You can create the opposite by installing a later ring gear in an
earlier unit. The speed sensor also was changed for model year 2004.
Complaint: Ford trucks and cars with 4R70W leaking
around mount area on rear extension housing.
Cause: The rear tail housing may be leaking in the area of the transmission
mount, above the cross member, You will likely find cracks in the tail housing
by the mount pads. This is almost always caused by the build up of corrosion
between the mount and housing. You will need a new housing and be sure to clean
corrosion from the mount. It can be a good idea to check by removing your
transmission mount before you have a leak and clean any corrosion away with
grinder etc to prevent the cracking and leaking.
Free shift kit upgrades for the Ford 4R70W and 4R75W that work nice
Here's some free information such as separator plate feed holes that can be drilled out and accumulator changes you can do to the valve
body: shift kit
Complaint: Slips in forward and or all gears badly, all
pressure regulator valve bore
may be worn out badly as well as the boost
valve and sleeve. if the main valve and body are worn then you'll need
a replacement valve body or there are reamer sets available thru Sonnax along with
2) The EPC solenoid may be faulty.
3) The Mass airflow sensor in the vehicle may be faulty which will command low
pressure to transmission. You may or may not have any trouble codes for the Mass air flow sensor,
and the only way to test may be to replace with a new sensor. You can test this
issue by unplugging the Mass air flow sensor and then drive the truck, if
you problem goes away and the trans feels better or firm shifting your problem
is not in transmission but in the mass air flow sensor. By unplugging the sensor
the TCM is setting a base value while missing the sensor signal. You will now
have sensor code in memory.
4) The pump can be worn out causing low pressure in transmission.