4R70W

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#1
Please fill out the following to ask a question.

MAKE:Ford
MODEL: F150
YEAR:97
MILES: 250000
ENGINE: 4.6
DESCRIBE ISSUE.... Started truck and had no forward movement until approximately 2800 RPM. Have reverse and had no previous issues with shifting or trans. Checked fluid and changed fluid and filter just to make sure it had the right fluid due to a line change by another mechanic.
 
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#2
scan for codes, yes even if light is out.

you have checked fluid- color, quantity?

do you have Reverse?

Do you have D1 - moving lever to low?
 

nickb2

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#3
As Kev said, scan for KOEO and KOER codes first.

If none, try a few things on this chart, like forward drive line pressure readings.

Shift linkage etc. This chart is for delayed/soft forward concerns.

Screenshot (832).png
 

nickb2

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#4
Here are locations for the line pressure taps. I am assuming it is a vin "W" engine. Anyway, even if it is a SOHC, same tap ports apply. Just need to know if it is a E4OD 4spd A/T.

Screenshot (833).png Screenshot (834).png
 

nickb2

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#5
If you have good reverse, that normally means the torque convertor is transfering fluid properly. So tapping the forward line pressure is a must.

You can also do air pressure tests. See snapshot below, apply air pressure to forward clutch, you should hear a thud. But you need a test plate for that. Not readily available.

Screenshot (835).png
 

bp042665

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#6
with my expert opinion pressure test is a must on these you could have a stripped input shaft on the forward drum if pressure is good suspect the shaft or just worn out clutches