4r100 differences

Addicted4 · Sep 2, 2015

Are there any differences between 99-03 7.3 diesel transmissions? I've been told that the 2000 model has its own but I didn't think there was.

Vader's Fury · Sep 2, 2015

Not to my knowledge. There is a ford HD version but that is the only difference I know of.

NC714 · Sep 2, 2015

I have very limited knowledge on transmissions, hopefully someone correct me if I'm wrong. I do believe one year model, between late 2000 and early 2001, had what was called a Mechanical Diode that was prone to failure. It is still a 4R100 Transmission.

Gunnnin · Sep 2, 2015

NC714 said:
I have very limited knowledge on transmissions, hopefully someone correct me if I'm wrong. I do believe one year model, between late 2000 and early 2001, had what was called a Mechanical Diode that was prone to failure. It is still a 4R100 Transmission.

Yes there was something about a diode. However when it goes bad, the fix was to go back to old setup. So they all interchange to my knowledge.

Mark Kovalsky · Sep 3, 2015

The early '99s had a different converter, lockup solenoid, and pump body. All late '99 and later are interchangeable.

Having said that, you don't want one from the first half of the '01 model year, unless it's been rebuilt. That's when they had the mechanical diode one way clutch. It was a disaster. The trans is interchangable, it is just that the mechanical diode has an extremely high failure rate.

Addicted4 · Sep 4, 2015

Thanks mark

10shots · Dec 29, 2019

Mark , can you tell me the difference in the. E99 pump body . I changed the front half that has the bushing and seal and now the transmission has soft shifts , needing to to figure this out

10shots · Dec 29, 2019

Mark Kovalsky said:
The early '99s had a different converter, lockup solenoid, and pump body. All late '99 and later are interchangeable.

Having said that, you don't want one from the first half of the '01 model year, unless it's been rebuilt. That's when they had the mechanical diode one way clutch. It was a disaster. The trans is interchangable, it is just that the mechanical diode has an extremely high failure rate.

Mark , can you tell me the difference in the. E99 pump body . I changed the front half that has the bushing and seal and now the transmission has soft shifts , needing to to figure this out

fastersteve · Dec 29, 2019

Also the diesel trannies have a larger output shaft. At least mine does.

Mark Kovalsky · Dec 30, 2019

I am not sure what differences there are between an early and later pump body.

10shots · Dec 31, 2019

4r100 pump

Do you think by me swapping pump half’s could cause a slight pressure lose , the transmission does not shift as hard and it very noticeable on the 3-4 as it slides then bangs on the shift at 3/4 throttle . I guessing there’s a issue with the pump half or a Teflon sealing ring

Mark Kovalsky · Dec 31, 2019

You could put a 0-350 PSI gauge in the pressure test port and see what the pressures are. Check at idle in every position PRND21 and at stall in RD21.