Freezing the Slushbox. Torque Converter on-demand lockup switch.

[RH77]

Another observation about Ford -- I just drove about 900 miles in the 2010 Fusion SE Auto. Great car by the way (good FE too... more on that later).

The transmission acts the same as the 1st-Gen, but with a 6-speed instead of 5. The strange thing:

Shifting to neutral coast at high speeds forces the engine RPM to remain where the final gear would be when you shift it back. So, it stays at 2500, in neutral for example, coasting at 70. So then, you shift back to D, and the revs are matched, already. My guess is that the TC is very involved with economical operation and free-wheels a bit.

Now, if you shut down the engine and coast, it doesn't like it all. It groans and generates a burnt smell. That was done once and that's it.

One nitpick: the old 5-speed had PRNDL only -- so "L" functioned as 3rd, 2nd, and 1st when it felt like it. Now, the 6-speed has an OD-off button that has a picture of a car going down a hill instead of an overdrive or gear reference. Shifting from 6th to 5th doesn't do a whole lot -- then we're back to PRNDL and 3 gears of mystery engagement.

RH77

[orange4boy]

Just filled up: 28 mpg. last tank: 30 Previous average: 24. Still getting a big increase in FE, although I think they switched to winter gas before the previous fill up. Got a big drop last year at about the same time. Will see next tank.

Biggest FE mod yet. I will have to try a highway P+G run to see If I can top 36mpg. Now that I can stay locked up in OD, It should work.

I hereby nominate this mod for inclusion in the List-o-mods. Anyone want to second it? Do I have to get all scientific first?

[Christ]

Scientifical is better, but those of us "in the know" have already done the math and understand the characteristic fuel savings that can be had.

I second the entry.

Due to the differences in vehicles, I'd rate it a 3 on the difficulty scale, and a 2 on the cost scale.

The job isn't Ninja, but the results sure are.

[taredog]

I finally found and installed a TCM from a 2004 Jeep Grande Cherokee. It truly has given me a second overdrive gear, 0.67:1. It was pretty much plug'n play.

Cost - $75 (US)

Concerns so far are that the 3-4 shift happens at just below 45 mph where before it was just below 40 with light throttle. The 4-5 shift happens just below 55. This would have been great during the summer but right now my commute on I-10 rarely stays above 55 for long. Due to I think snow birds, school and contractors adjusting their work hours to the sun. Plus four miles of 40-45 mph urban streets. It is also hard to tell if I am in 3rd or 4th, guess I need to figure out an indicator system. Time will tell if this mod is actually helping or hurting my FE. I am sure it will help on long trips.

Now, after being side tracked for months, on to the original goal, locking the TCC. Logistically it's kinda a pain as the TCM is behind the right head light and the lockup solenoid connector is on the trans. I really don't want to cut in to the wiring harness. Maybe there is a connector between the two. Time to get dirty

[cighon]

so how do you know when your auto trans has locked? the RPM? sound of the engine? or do you need a diag. tool (ScanGauge)?

[taredog]

Originally Posted by cighon

so how do you know when your auto trans has locked? the RPM? sound of the engine? or do you need a diag. tool (ScanGauge)?

The first two. Scangauge X-gauge function for TC lockup only works for some vehicles. Just pay attention as you accelerate gently and see how the RPMs drop or the engine sound changes. Don't do it in a high traffic situation. It helps to know how many gears your transmission has too.

[IsaacCarlson]

If so, did you disable one or use both? And how.

[RH77]

I finally got around to trying this and it works great...

Background:

My TC is a 2-solenoid type, "A" and B". There is essentially one wire into each solenoid, at +12V, that activates each. The shop manual mentions that a "click" should be heard if the lead is applied to battery voltage. Each one demonstrated the clicking sound and is working properly.

3 levels of lockup occur under normal operation, with full lockup at 35 mph under modest throttle. With both activated, lockup can be half (stage-2 of 3) at light throttle or idle. Full lockup (3rd lockup stage) kicks-in after that. (This comes in very handy later...)

Modification:

The 2 lockup wires were cut just before the connector to the solenoids (the source wires from the TCU were isolated). The two wires to the TC were tied together, and hooked to a wire that was run into a toggle switch on the dash. On the other side of the switch, a wire was run from a temporary battery clamp. With the vehicle off, the clicking sound coincided with the throwing of the switch. When not in use, the clamp is removed from the battery to prevent drain.

Operation:

Check Engine Light and Transmission "D4" light blinks indicating a transmission fault.

The vehicle runs normally without the switch engaged (but with no TC lockup).

Flipping the switch engages partial lockup at any speed or gear (including while stopped).

When Stopped: Engine speed decreases 200 RPM, but idles smoothly.
Acceleration from Stop: Just after starting out, the TC fully engages at about 1200 RPM. Each gear shifts as expected, but more harshly and at lower RPM based on throttle input.
Cruise: Very light throttle uses only partial lockup. Full lockup occurs with modest throttle (in every gear), with a noted increase in FE a lower speeds and the engine lugging similar to a vehicle with a manual transmission. It was possible to cruise in 4th gear, Full TC Lockup at 20 MPH using only idle throttle (Note: 9 TPS = 0% throttle input; 90 TPS = 100%). At 11 TPS, full lockup occurs and gives that "direct connect" between engine and road. This mod definitely allows higher engine loads, lower speeds, increased FE, and a more "manual transmission" feel at city speeds. At highway speeds, the TC remains locked.
Downshift: A generous throttle input kicks-down to a lower gear as normal, but the action is pretty harsh. With the TC engaged, there isn't a lot of shock dampening. It's also better to "lift shift" for normal acceleration gear change.
Deceleration: Decel is normal until you get down below 35 MPH. From 35 to a stop, the transmission shifts at the latest stall speed, with some lugging and vibration noted. Flipping the switch to disengage lockup will allow longer DFCO decels and smoother downshifts with a more economical idle.
Stopping: Even if the switch is forgotten, the transmission will shift down through each gear to first, but very late and abruptly. Once stopped, the TC is partially engaged and idle speeds are slower, but the vehicle does not stall.

Conclusion: This is great! I finally have control over the pesky TC. The plan is to mount the switch on the shifter stalk, locate an accessory-only power source, and install some inline diodes with a "Master Power" switch to operate the transmission normally or in Manual TC or "MTC" mode

RH77

[Christ]

Rick -
My only concern is that the TC clutch is actually slipping while at idle, which might be wearing it.

For the sake of the clutch, I'd probably install a throttle switch so that the power was cut if the accelerator isn't being used, or if the brakes are applied, either way.

[Formula413]

Originally Posted by Christ

Rick -
My only concern is that the TC clutch is actually slipping while at idle, which might be wearing it.

For the sake of the clutch, I'd probably install a throttle switch so that the power was cut if the accelerator isn't being used, or if the brakes are applied, either way.

+1 I would allow the TC to resume normal operation at a stop or very low speeds, the TCC is clearly not designed to handle so much slipping. Under normal conditions it would see much less slippage then even a traditional clutch in a manual transmission since it would only lock when input and output speeds were very close to unity, and unlock under heavy loads.