O/D off switch relocation

The PCM is set up for roughly the following behavior:

3-4 shift occurs at about 35 MPH (exact speed varies per calibration; if your speedo says something way off, it's probably just an inaccurate needle placement)
TC locks over about 2 seconds, assuming TC slip as the TCC applies does not exceed a certain threshold (in which case the shift will complete and the TC will remain unlocked until the slip drops below the threshold)

A 4-3 shift occurs at about 32 MPH.
The TC will unlock in 4th gear before the 4-3 shift, usually at around 33.5 MPH (again, varies with calibration). The TC will lock again when speed exceeds 36ish MPH.

With a cold TOT (usually under about 50F, again this varies) the converter will stay unlocked. The 3-4 shift point is also lower - about 32 MPH.

The upshift speed is always a few miles above the downshift speed.
 
I was told this was yuck. That was all the motivation I needed!

Feels like paddle shifter before there were paddle shifters. Feels like a Ferrari.

Ok...seriously, I know this has a bit of a vibe of a disability accommodation. But I love the functionality. Few snapshots, because it's getting dark, and I need to clean up. It's wired to trigger O/D regardless which direction I push it, though pushing it down feels most intuitive.

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theterminator93 said:
The PCM is set up for roughly the following behavior:
Click to expand...

Are you saying specifically V6? Or regardless of engine. Note that my PCM is from a very late '97 which, according to the sticker, had the very late tune (starting with a 7 iirc).

theterminator93 said:
3-4 shift occurs at about 35 MPH (exact speed varies per calibration; if your speedo says something way off, it's probably just an inaccurate needle placement)
TC locks over about 2 seconds, assuming TC slip as the TCC applies does not exceed a certain threshold (in which case the shift will complete and the TC will remain unlocked until the slip drops below the threshold)
Click to expand...

3-4 always occurs at about 39-40 with light throttle (same with both PCMs), and there's no speedo inaccuracy (GPS confirmed). The TCC is already locked at this stage; it usually locks simultaneously to the 2-3 shift. However, what you're describing matches the behavior of my '06 Crown Vic.
The only a 3-4 shift occurs earlier (though without TCC lockup) is cold start + cold ambient temperature.

theterminator93 said:
A 4-3 shift occurs at about 32 MPH.
Click to expand...

This about matches my observations.

theterminator93 said:
The TC will unlock in 4th gear before the 4-3 shift, usually at around 33.5 MPH (again, varies with calibration). The TC will lock again when speed exceeds 36ish MPH.
Click to expand...

TCC unlocks when speed falls below 38-39 and relocks at the same speed.

theterminator93 said:
With a cold TOT (usually under about 50F, again this varies) the converter will stay unlocked. The 3-4 shift point is also lower - about 32 MPH.
Click to expand...

As I said, this matches my observations.

theterminator93 said:
The upshift speed is always a few miles above the downshift speed.
Click to expand...

I mean I get that. I'm not saying it's a malfunction. It just annoys me.
We have this long stretch of flat road here where you cruise for maybe two miles at a consistent 35 mph. In one direction, the Bird wants to go in 3rd (because I start out from a neighborhood street); in the other direction, it wants to go in 4th (because I come off the freeway). Maybe I'm too aware of my car; maybe I should listen to music instead.
I somewhat understand the rationale...I guess, reducing the number of shifts? But I feel it's the exact same scenario; there has got to be the ideal gear to be in.
 
Grog6 said:
the switch is a simple spst momentary switch; putting another one in parallel will work fine.
Click to expand...
I did exactly this when i relocated mine. I bought the switch locally, at an electronics supply store, but it's basically this same switch from amazon
1 side of switch is fused switched 12v, other side goes to ECU.
Mine is just mounted to the side of the shifter body, i added a light too that comes on when O/D is off.
 
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1997ThunderbirdLXV6 said:
I was told this was yuck. That was all the motivation I needed!
Click to expand...

Nicely done, looks better than I was expecting!

It wouldn't last long in my car.... After driving Panther platforms and Ford trucks for that better part of my life; I'd be trying to slam that stalk into drive. Muscle memory still has me trying to reach for a column shifter in my Cougar sometimes, and it's not even an auto anymore. :facepalm:
 
Kenz said:
It wouldn't last long in my car....
Click to expand...

I know! If I ever lend my car to a friend, I will have to instruct them on what it is. Not a shifter; not the wipers...

I'd like to add an "O/D OFF" script to it, but I'm not sure how to do that well. Maybe there's some sort of press on lettering I could use.
 
SuperHawk said:
Put a button on the backside of the cruise control switch housings. Mark VIII clock spring,
Click to expand...

Yes, I did consider that option, with a steering wheel-mounted shift paddle. That would have been the optimal solution.
To be honest, I was a bit intimidated by having to mess with airbag wiring, but this may still become a future upgrade.

For now, I'll see how I like the current configuration with the stalk. Haven't had much of an opportunity to test it. I do like that it's in the same place regardless of steering angle
 
messing with the airbags isn't dangerous, IF you take precautions.
1) disconnect the + battery terminal, and wait a half hour. This lets the caps in the airbag controller discharge.
2) if you're dinking with the dash or steering wheel, remove that airbag. when you unplug it, there are shorting bars in the connector on the bag.
3)NEVER probe the connector on the airbag.

These things make it as safe as dealing with explosives gets.
Do the reverse to hook it back up.
 
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