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1991 7.3 idi E40D transmission swap ?

4K views 9 replies 5 participants last post by  oldrebuiltdodge 
#1 ·
Does any one know what manual transmission could replace an auto E40D transmission? (4X4)
 
#2 ·
I don't know if there is an automatic out there that will work, but the ZF-5 Manual will work nicely. You'll need the flywheel, and clutch assemblies to go with it though
 
#3 ·
If you can fab the mounts and engine adaptor, you can probably use any transmission you desire. I've done a couple Dodge/Cummins auto-to-manual conversions. Those were pretty straightforward. Not so sure on the Ford. With s lockup convertor, I'll stick with the slightly higher OD ratio.
 
#4 ·
None, unless you drive it like an F150. The E4OD is rated for 1,000 lb-ft of torque, and it will actually handle more than that. No factory stickshift comes close. The ZF is only rated for 420 or 470 lb-ft.

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#5 ·
None, unless you drive it like an F150. The E4OD is rated for 1,000 lb-ft of torque, and it will actually handle more than that. No factory stickshift comes close. The ZF is only rated for 420 or 470 lb-ft.
You're comparing apples to oranges. The E4OD was actually rated lower than 1,000 lb-ft. If I remember correctly (and it's been two decades, so maybe not) it was rated around 900 lb-ft.

This rating is at the input shaft after the torque converter multiplies engine torque. The torque multiplication of the E4OD converter was 1.9:1. So 900 lb-ft divided by the torque ratio of 1.9 gives a crankshaft torque rating of 473 lb-ft. That's right where the ZF trans is rated.

So yes, the ZF is a good choice for this application.
 
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#6 ·
My first statement was based on the fact that in '96-97, the E4OD was simply renamed 4R100, in accordance with Ford's (then-)new transmission naming scheme. My second was based on the MANY anecdotes I've heard & seen (IRL & on YouTube) of 7.3s being boosted to much-higher torque than stock, and their E4ODs/4R100s tolerating it.
 
#7 ·
The E4OD was renamed 4R100 when the Superdutys came out in 1998. At that time many of the internals were updated to upgrade the torque rating.

Ford's torque rating intends that the trans can handle the rated torque running at maximum GCWR for the design life of the trans. I'll bet a boosted 7.3L will tear up an E4OD or 4R100 if running max GCWR for 200,000+ miles.
 
#8 · (Edited)
Good to know.

So is the transmission's rating @the flywheel? Or @the input shaft? I always assumed it was the former so it would be easier to match it to an engine.
 
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