Hard gear shift Differential ratios
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Freshman User
Joined: Oct 2002
Posts: 45
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From: Ontario
Hard gear shift Differential ratios
I have just finished installing an 302 V8 engine and and four speed automatic trany from a 91 F150 into my 64 pickup. My differential is from the 64 with a set of 4:10 gears, I am planning to change over the differential from the 91 that has a set of 3:55 or 3:56 gears. The 91 truck had a trailer package. What would the ratio be for a none trailer package truck.
Does the 4EAO tranny hard a hard shift?
Does the 4EAO tranny hard a hard shift?
Cargo Master
Joined: Jan 2004
Posts: 2,512
Likes: 8
From: Cook Forest and Irwin PA
the rears were whatever were ordered - trailer tow or not. the 5.0 IIRC had 3 options in 91 - 3.08, 3.55 and 4.10, and each ratio had a tow rating.
I dunno what a 4EAO tranny is, in 91 the autos were AOD and E4OD. The E4OD isnt doing much shifting without a PCM. Did you graft everything including the EFI?
I dunno what a 4EAO tranny is, in 91 the autos were AOD and E4OD. The E4OD isnt doing much shifting without a PCM. Did you graft everything including the EFI?
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Freshman User
Joined: Oct 2002
Posts: 45
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From: Ontario
Hard shift
Sorry I got the model to the tranny mixed up. Yes I have grafted the ECM into the old truck along with fuel injection.
The first to second shift is at about 10 to 15 MPH even when I put the foot on the floor, it's into overdrive by the time it gets to 40 MPH.
The first to second shift is at about 10 to 15 MPH even when I put the foot on the floor, it's into overdrive by the time it gets to 40 MPH.
Junior User
Joined: Nov 2001
Posts: 93
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From: Grove City, PA USA
In 91 most 302s had AOD in them. It may be the AODE which had electronic controls, not just the TV cable.
I believe that the 64 truck has the 9 inch rear in it. I would keep it if you don't need the tone ring for the electronics. It is not hard to find other center sections with different ratios to swap.
just my thoughts.
I believe that the 64 truck has the 9 inch rear in it. I would keep it if you don't need the tone ring for the electronics. It is not hard to find other center sections with different ratios to swap.
just my thoughts.
FTE Legend
Joined: Jun 2006
Posts: 31,930
Likes: 1,499
From: Ottawa, Ontario
Sounds like the computer is not getting the speed input it requires from the vehicle speed sensor(VSS), this makes the computer go into limp mode and max out the tranny shift pressure in an attempt to prevent damage. The VSS would have been on the tranny tail shaft or in the rear axle, so if your tranny doesn't have it you may need to put the '91 axle under there and connect the RABS/VSS sensor to the computer.
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Freshman User
Joined: Oct 2002
Posts: 45
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From: Ontario
Hard shifting
It is the electronic tranny and the speed sensor is working as I have an electronic speedo (the problem excited before the speedo was installed).
The rear axle is a Dana 44
The rear axle is a Dana 44
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Cargo Master
Joined: Jan 2004
Posts: 2,512
Likes: 8
From: Cook Forest and Irwin PA
change the speedo gear to 23 teeth from transmission center and see if that helps - they have a specific part number to allow these to run with 4.10 gears.
AOD, AOD Performance Transmissions from PATC, AOD Transmission, AOD Mustang, AOD
3.55 'thinking' electronic tranny in a 4.10 world means about 15% lower shift point. the pcm thinks you are going faster than you really are.
AOD, AOD Performance Transmissions from PATC, AOD Transmission, AOD Mustang, AOD
3.55 'thinking' electronic tranny in a 4.10 world means about 15% lower shift point. the pcm thinks you are going faster than you really are.
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Hotshot
Joined: Jul 2002
Posts: 14,285
Likes: 12
From: Bend,OR
Ford Fuel Injection might have some info on this as well. you probably would be better off pulling that E4od and placing an AOD in its place which isnt controlled by the computer at all.
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d0n_3d
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Dec 18, 2003 04:23 PM