Torque Converter Lock/Unlock

[Sburn]

Interesting subject. Like Jack, I drive a gasser, so it's not always apples-to-apples with the diesel rigs.

But on the subject of T/C locking/unlocking, I was going though the transmission part of the factory service manual (2007 F150) one day. Ford's own transmission road test procedure suggests that the T/C should stay locked when letting off the gas above ~40MPH and unlocking only when the brakes are applied. But my truck has never done this, either when stock or w/ Gryphon. Letting off the gas unlocks the T/C, brakes or not.

From what I've read here and other places, it doesn't sound like anybody's 2004+ F150 stays locked when tipping out of the gas. So who knows what Ford was thinking...

[cleatus12r]

The concern here is Ford. There are SO FREAKIN' MANY different strategies that do so many different things that it will make your head spin .

Here is a list of a few different things Ford did with their diesel trucks concerning shift strategies. Some were this way, others were not.

1. No lockup in 2nd gear no matter what accelerator input or road speed.
2. No lockup in 3rd gear until 45-50 MPH. Though by that time, it was in 4th gear under normal driving conditions anyway.
3. TCC unlock when accelerator pedal released. Relock when back into it.
4. TCC unlock with brake input. Relock when brake released.
5. TCC remain locked during either of the above conditions.
6. TCC unlock for 2.5-3 seconds during 4-3 downshift.
7. None of the above.

The shift/TCC strategy that gabeyd is referring to will apply the torque converter clutch on acceleration around 35-40 MPH. After that, it remains locked (or unlocks/relocks so fast that it's not perceived as an unlock/relock event) at any speed above 30 MPH...even on decel from 4th to 3rd at around 40 MPH. This strategy works well for most people and is essentially how PMT1 works right out of the gate. There are a lot of modifications that can be made to make it work even better.....but the base program is what makes the difference. However, I am pretty sure that PMT1 doesn't have the ability to run a glow plug control module like the Excursions have.

I want to say that DJ (soutthpaw) is running the EBM1 calibration in his Ex but Bill would know for sure.

[gabeyd]

Originally Posted by cleatus12r

I want to say that DJ (soutthpaw) is running the EBM1 calibration in his Ex but Bill would know for sure.

Maybe that's what my old chip had, I don't know. I don't really know them by the calibrations, I just know that everyone talks about PMT1, and that it leaves the torque converter locked much more. That's what I want... Don't really care if it's actually PMT1, or some other calibration that shifts similar or the same. I know that the shift strategy that I have on my new PHP chip is very similar to my stock strategy as far as TC lock goes, and I know I don't like that...

[soutthpaw]

Originally Posted by gabeyd

Maybe that's what my old chip had, I don't know. I don't really know them by the calibrations, I just know that everyone talks about PMT1, and that it leaves the torque converter locked much more. That's what I want... Don't really care if it's actually PMT1, or some other calibration that shifts similar or the same. I know that the shift strategy that I have on my new PHP chip is very similar to my stock strategy as far as TC lock goes, and I know I don't like that...

Thanks, Cody sent me a PM to read this thread.. yes I have EBM1 though stock for my Ex is EBM3 you have to disable or reprogram the PATS System if you go to EBM1 if it was not the original PCM code for your truck... as for it locking and unlocking Ill have to drive my truck and check what it does.. but the EBM1 is the Excursion equivalent of the PMT1. Cody is also correct about Glow Plug Control Module... only found on CA trucks but all 50 state Ex's

right now i have 60 80 and 100 on my truck dont have FS on right now.. I'll have to get the 40 from bill, don't have it for my PCM code for some reason. my FS is 75 so Ill check with Bill and see if he has the 80FS not sure what differences it has if any

[cleatus12r]

Thanks, DJ!

[gabeyd]

Thanks DJ.

I don't think it anything to do with which program I have, it does it on all of them. So you don't need to try out 40T and 80FS unless you want to. But I would appreciate you checking and seeing how the TC behaves on your tunes.

I was under the impression that the shift table could be copied over from a PMT1 to whatever code was needed on a truck? I didn't think I would have to switch entire PCM codes... But, I'll probably end up giving Bill a call after his no phones week and see what my options are if he doesn't jump in on this thread.

Thanks.
-Gabe

[Power Hungry]

I'm in the gameroom if you'd like to chat about it.

[Jackpine]

Originally Posted by Sburn

Interesting subject. Like Jack, I drive a gasser, so it's not always apples-to-apples with the diesel rigs.

But on the subject of T/C locking/unlocking, I was going though the transmission part of the factory service manual (2007 F150) one day. Ford's own transmission road test procedure suggests that the T/C should stay locked when letting off the gas above ~40MPH and unlocking only when the brakes are applied. But my truck has never done this, either when stock or w/ Gryphon. Letting off the gas unlocks the T/C, brakes or not.

From what I've read here and other places, it doesn't sound like anybody's 2004+ F150 stays locked when tipping out of the gas. So who knows what Ford was thinking...

Not trying to hijack this thread, but Sburn, have you noticed that the TC will remain locked when you're coasting downhill with the cruise control on? (At least mine does). So it attempts to hold the speed in this situation. Tap the brake (releasing the cruise control) and the TC immediately unlocks.

Wonder if the diesel strategy is the same?

- Jack

[Sburn]

Originally Posted by JackandJanet

Not trying to hijack this thread, but Sburn, have you noticed that the TC will remain locked when you're coasting downhill with the cruise control on? (At least mine does). So it attempts to hold the speed in this situation. Tap the brake (releasing the cruise control) and the TC immediately unlocks.

Wonder if the diesel strategy is the same?

- Jack

Jack, that's exactly what happens in cruise.

Other thing I've noticed it that, under certain conditions, the trans will go from 4th unlocked to 3rd locked instead of the more usual 4th unlocked -> 3rd unlocked. Condition seems to be: long uphill, no cruise, 50+ MPH. Key thing might be time under a certain load. It does not behave that way on my daily commute going up the same percentage grade on a somewhat short grade. But out on the Interstate, where that percentage grade might go on for miles, it will do the 4th-U - > 3rd-L shift. Some flavor of TFT control, perhaps?

As for thread hijacking, I get the impression that Cody knows his transmission stuff cold ans seems happy enough to talk about it with us.