Hey mike i have an 04 duramax with a stage four suncoast for the last month it has wants to shift up to overdrive way sooner than it should under less than full throttle. what does this sound like to you. ????????
Tranny shift problem
- Thread starter dracing70
- Start date
so what does this mean mike the stock tranny tune is back in and it is better compared to the stock 01 tune i had in. it was absolutely horrible it shifted to overdrive at like 45 miles an hour under power. my stock is way better but still not the way i think it should be it never used to be this way.
With out knowing what you have done to your truck, I have no idea. Something changed as far as electronics. Tuning, speed sensor, TCM. All the shifts are controlled electronicly so we have a control proplem.
It sounds like you're commanding too much fuel too soon in the rev range. The trans shifts vs. TPS, not actual fuel quantity. If you're commanding a lot of fuel at part throttle then the truck will reach it's 'shift mph' quickly, also- the 'shift mph' will be artificially lowered on account of the low throttle position.
In summary, raise your part throttle shift speed in the TCM or adjust your fueling curve to hit later in the throttle travel.
Nick
In summary, raise your part throttle shift speed in the TCM or adjust your fueling curve to hit later in the throttle travel.
Nick
Try it with a stock tune to isolate the problem.
If it does it with the stock tune, adjust the TCM tuning.
If it only does it with a modified ECM tune, adjust the ECM tuning.
If it does it with the stock tune, adjust the TCM tuning.
If it only does it with a modified ECM tune, adjust the ECM tuning.
thanks guys at least someone finally answered my question and gave me some insight to maybe fix my problem