Auto Gearbox Question

[Black_Bug]

Hey everyone been trolling this site for a while and theres alot of usefull info on here. Can anyone confirm the following.

I was talking to an auto wrecker about my fiance's VY V6 Trans & basicly i can shift quicker in my manual than this thing. But my parents who have the same car shifts really well. I was told Holden had a tendency to tune the cars differently. He suggested one way to overcome this was to remove the driver kickboard and swap the trans computer with another that shifts hard (i.e. my parents) and then her trans should shift like theirs?

Can someone confirm?

[SweetWagon]

It wont work as the PCM is security coded to match the vehicles BCM.

[Black_Bug]

Ok thanks mate

[TMM]

The transmission software employs a learning program which adjusts the shift points (rpm) and consequently line pressure (firmness of shift) according to driving style.

If you drive your car like you stole it then it will push up the shift points and line pressure accordingly. You can make it re-learn faster by disconnecting the battery for 30mins, then driving it fairly hard.

The GM 4L60E auto trans that Commodores use are known to have an intermittent issue with harsh shifts from 1st to 2nd where the shift is delayed and then it slams it into 2nd gear like you wouldn't believe - can be caused by a worn out throttle position sensor. If your parents don't thrash their car then that is probably why their car seems to shift hard. Mine does it from time to time, once it did it hard enough to chirp 2nd at WOT and kick the car out sideways on a straight road up a slight hill (with an open diff!)... that was fun. Since putting in fresh trans fluid it doesn't do it so often, or as brutally.

[Black_Bug]

Neither cars a thrashed or anything, the only time the get a workout is when i drive but not just 1-2 but all gear transitions have a 2-3 second delay but it doesnt surge into the next gear. Even when driven hard it doesnt shift well.