AW-70L Manual Shifting
 

Good day.

Been some time since posting, and had what could be considered a "performance oriented" question for the community.

I have the possibility of laying hands on an immaculate 1990 740 which has the stock AW-70L (Toyota A42DL?) transmission. By the specs, this transmission unit features completely hydraulic shift actuation, with the exception of an overdrive solenoid for 3>4 transition.

I am one of those curious folk who appreciates "walking" my automatics through the gears manually; directly removing all load from the clutches on each upshift. There's a little dance with the stick, throttle, and winter switch which I use on our 95 960 to achieve this; and the results are quite good: Less wear, lower temps, better power control across the board. I can also selectively skip granny and just lock in 2nd for less hassle in slow traffic.

The 70L would seem to be a bit of a challenge with regard to any such usages as traditionally implemented. However, I could adapt well enough if there is a modification which might be known to allow for simple, exclusive manual shifting of this unit. All automatic gear-change functionality (apart from converter lock-up) could be eliminated to achieve this end: I wouldn't miss it one bit.

As a "quick fix" I have considered disconnecting the kick-down cable and locking it into a "closed throttle" position to allow better overriding manual control of upshift points. However, I have some concern about also reducing final lockup pressure on the clutch packs by doing this, resulting in slippage after final engagement. I might be wrong here, perhaps someone could shed some light on this type of scenario, too.

In sum, I would appreciate knowing:

• if there is a throttle body (or other) modification which will allow permanent, selective manual upshifting of the AW-70L; and
• if running this transmission with the kickdown cable permanently slackened simply changes shift points and "softens" the shift transitions, or if it will also cause a reduction in hydraulic pressure on the clutch packs when fully engaged.

Thank you so much.