1999 Torque converter lockup versus computer code rev.

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Jan 8, 2003 | 11:44 AM

rafterjf250

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From: Washington

1999 Torque converter lockup versus computer code rev.

I have a 1999 F350 Turbodiesel, currently with computer code revision NVK2. In this combination, torque converter lockup occurs relatively late and releases reasonably early.

As I understand it, later models (2000 and beyond)lock the torque converter sooner, release it much later, and (for example) execute a smooth downshift sequence automatically if, say, one were to be going downhill and take their foot off the accelerator. Those of us with 1999s know that after we take our foot off the acelerator, we go into freewheel mode pretty quickly.......which is a big disadvcantage when going downhill.

My question is this, for anyone who might know: if I upgrade my 1999 with NVK2 code to NVK4, NVK5, or NVK6 code, will my torque converter lockup characteristics change and be more like the later models ? Or are these torque converter lockup characteristics of later models accomplished through some mechanism other than the NVKx computer programming ?

Thanks in advance.....

JimR

Jan 9, 2003 | 12:55 AM

charlez

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From: Nebraska

1999 Torque converter lockup versus computer code rev.

Torque Converter lock up is controlled by the PCM (computer). :7

Jan 10, 2003 | 05:01 PM

rafterjf250

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From: Washington

1999 Torque converter lockup versus computer code rev.

I agree that torque converter lockup is handled by the PCM....it's that way in my current configuration.

Really the question would be that changing the PCM code revision from NVK2 to the version present in 2000 and later models is going to make my 1999 F350 perform (from a torque converter lockup and shifing perspective) like 2000 and later models ?

Thanks....

Jan 10, 2003 | 09:56 PM

kspilkinton

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From: South Kitsap County, WA

1999 Torque converter lockup versus computer code rev.

The newer cal code will work to change the lockup and other characteristics, IF the newer trucks have the same TC that your model does, and that is all the cal code modifies. So, as long your '99 has the same layout(sensor paths/memeory addresses in the computer) and the parts actually in the engine and transmission haven't been upgraded in the newer models (increased performance or parts redesigned), it should work. I'd consult with the Ford mechanic first to see if the upgrade of your cal code is workable.

Also, the PCM has a learn characteristic. If you disconnect your battery, it wipes this memory out. The PCM uses the memory to map out how to control the tranny (up shift/ down shift) and the engine to provide what engineers deem as useful power and provide for fuel economy. If you drive under varying conditions, I don't know that this "memory erasing" will do any good. Since learning of this myself, and "erasing" the memory, I've got the truck "trained" to "down-shift" down steeper grades. It doesn't shift a gear down, but it drops like the torque convertor is locked up.

Jan 11, 2003 | 08:25 AM

Mark Kovalsky

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From: SE Florida

1999 Torque converter lockup versus computer code rev.

> Also, the PCM has a learn characteristic. If you
>disconnect your battery, it wipes this memory out. The PCM
>uses the memory to map out how to control the tranny (up
>shift/ down shift) and the engine to provide what engineers
>deem as useful power and provide for fuel economy. If you
>drive under varying conditions, I don't know that this
>"memory erasing" will do any good. Since learning of this
>myself, and "erasing" the memory, I've got the truck
>"trained" to "down-shift" down steeper grades. It doesn't
>shift a gear down, but it drops like the torque convertor is
>locked up.

That isn't true on a 7.3L diesel. Those PCMs do not learn.

On the gas PCMs and the new TorqShift all they learn is how long it takes from when the PCM requests a shift until the shift completes. Then it adds or subtracts pressure for the next shift to get the slip time back to ideal.

Ford PCMs do not learn to change when they shift, just how long the shift takes.

Jan 11, 2003 | 05:48 PM

kspilkinton

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From: South Kitsap County, WA

1999 Torque converter lockup versus computer code rev.

That's why your the tranny engineer... learn something new from Mark every time... thanks, Mark, for setting me straight.

Can he still upgrade the cal program?

-Kerry