Finally got around to trying my crazy idea above on my 2001 Double Cab. In the process, I discovered that the FSM has an error regarding which plugs from the engine harness enter the ECU at which locations. <img src="/forums/images/graemlins/angry.gif" alt="" /> Once I sorted this out, I did the shift part of the mod as I outlined above.

It works as advertised. With all switches down, the tranny functions normally. Flip the first switch, and you get 1st, 2nd switch gives you 2nd, etc. <img src="/forums/images/graemlins/kewl.gif" alt="" />

BUT... the ECU monitors continuity to the shift selenoids on a two-trip basis, and also monitors whether the tranny is actually in the gear that the ECU is trying to shift to. This throws a code(s) P0753/P0758, AND causes the ECU to go into fail-safe (i.e. manual) operation mode until the code(s) are cleared with a scan tool. <img src="/forums/images/graemlins/frown.gif" alt="" />

Therefore, once you shift back out of manual control (switch #1 flipped back down), you have to clear the codes, or the ECU won't shift your tranny. <img src="/forums/images/graemlins/angry.gif" alt="" /> Instead, you get 4th (OD) gear with the shifter in "D", 3rd gear with the shifter in "2", and 1st gear with the shifter in "L". (You also get no converter lock up either, so if you do this mod, you'll need to also fab a circuit to control the converter while in manual mode.)

As stated above, my ScanGauge II lets me reset the codes on the fly, so not a big deal for me, but would be a huge pain for anyone who doesn't have a scan tool hooked up most/all the time.

My guess is the AW Shifing controller would suffer the same issues with codes (at least on newer vehicles -- not sure which year the ECUs started monitoring the selenoids/gears). <img src="/forums/images/graemlins/confused.gif" alt="" />

My bottom line is, unless you have an overriding need to force the tranny into a specific gear (i.e. forcing OD and lock up while pulling a trailer), this is more work and trouble than it is worth. <img src="/forums/images/graemlins/shame.gif" alt="" />

Jake,have you had any further problems with your controller?I am getting ready to install mine.I am just curious about how your controller is working out for you.

no problems, Brett said it may be some relays that got stuck open...but then again i havent driven my truck in 2 weeks, put a custom radiator in and have been fighting the hoses until tonight... <img src="/forums/images/graemlins/shiner.gif" alt="" />

Just for completeness of the thread, the other shop that does the A340F upgrades to compete with Level 10 is IPT Transmission:
www.ipttrans.com
That's who I had upgrade my 4Runner's valve body. No complaints here.

Okay. Finally got around to implementing my crude manual shift control (schematic in thread above). Decided to go with only a toggle for the converter lock-up. Mounted the box w/switches on the front of my upper console, where I can comfortably reach over the edge to flip the switches with my arm resting on the console.



The switch nearest the driver is the converter lock-up: down connects the converter selenoid to the ECU, up sends 12v to lock the converter.

The next switch selects ECU (down) or manual (up) control, as well as sending 12v to selenoid #1 only for 1st gear when in up position. The other three switches progressively select 2nd, 3rd, and 4th as you switch them up (as long as the first switch remains in the up position).

The downside is the ECU in my 2001 Taco almost immediately throws a code when you use either the manual shift control or the converter lockup control. No big deal as long as you continue to shift manually, but if you flip the switches back to ECU mode, the ECU stays in "fail safe" mode and won't shift automatically or lock the converter until you re-set the codes. I have a semi-permanently installed ScanGauge II, so can do this on the fly, but would be a major PITA if you didn't.

The upside is that the system works great with the trailer behind, as I can force 4th gear and lockup under significant load (where the ECU would always down-shift and unlock the tranny -- causing major heat issues). Driving with OD off (as suggested in the owner's manual) results in about 3000rpm at 60 mph -- effectively limiting top speed. With manual control (4th and locked), I was able to run 70+, and get comparable gas mileage to when I used to run 55-60 in 3rd.

Here is my rig, so you can get an idea of what I'm putting behind my Taco. I've got a S/C, 7th Inj, TRD Headers, and TRD Cat-Back, so the size of my trailer is less an issue than it would be for a stock truck.