How can I reprogram the shift points in a 2000 Olds minivan?
 

I would like to reprogram the shift points for the tranny in our 2000 olds minivan for improved fuel economy. Does anybody know how I could go about doing this? What equipment do I need? Program?

Speedy:)

I opened this thread hoping to see another gearhead hot rodding the family car, and what do I find? Economizing! WTF? :eek:

Sorry. I hope you can get the answer you seek. :D :D :D

No kidding...I was hoping for, "Vans Gone Wild":)

"Reprogram shifts points...for improved fuel economy", on a minivan: I didn't know you could be neutered twice:)

Target maket size for that software? 1.

And my guess is you are unlikely to make significant saving in fuel economy.

We are getting soaked $150 a week in gas costs and we are living on a limited budget since I am going to school.

Speedy:)

I am estimating about 10% for mixed driving.

Speedy:)

Ouch.:D

One word.

Hydrogen Gererator.

Drive less? Buy a Civic? Motorcycle? Bike?

Math was never really my forte', but..........

10% seems optimistic.

Why wouldn't GM do that from the factory? What are you going to sacrifice in drivability to get that?

But you can get 10% by doing maintenance, and driving carefully.

These suggestions have already been implemented with the exception of the motorcycle. I have one but will not ride it any longer due to safety concerns. Even though I don't have a Civic I do have a crappy Saturn which I may swap out final drive ratios for a SL1 gearing.

Speedy:)

I find it hard to believe a manufacturer leaves 10% fuel economy on the table due to shift points.

Shift it manually for a while to test your theory.

I have gone from 22 mpg to 26 mpg by driving s l o w e r (AKA speedlimit)

What I want to do is..
1)Have it hold OD longer during slightly more throttle input like going up a hill
2)I want it to immediately shift back into OD during throttle lift off and reapplication. Right now it takes 2 seconds to shift back into OD
3) lower rpm shift points for 2nd and 3rd gear during light throttle applications. 4th seams OK as it is.
4) lower the temperature the engine has to reach before the tranny will shift into OD during cold start. This alone will see an increase of %50 during the first 3 miles driven.

Speedy:)

Just a hunch, are you getting an engineering degree?

Mechanical Engineering :)

Speedy:)

You're worried about a 2 second lag in OD shift?

Oversize tires pumped up to 45psi

Cardboard in front of radiator to get it up to temp faster.

Tires pumped up to 45 psi... Check! already done.
Cardboard in front of radiator.... Check! done in winter time and taken out now.


Anybody know how to go about getting the software to do this????

Speedy:)

We all have it we're just not going to share it until you graduate. SmileWavy

Good luck with this, the tool for accessing the computer portion of the GM transmissions comes in a huge suitcase, and its very, very, proprietary. A modification of the governor valve would be easier.