Recently i have been noticing my car wont shift gears until it hits 3500 rpm (give or take a few) i was told to get it hooked up to a computer at a trans shop,dont have the $$$, was also told to replace the vacumn modulator, did that and nothing...same thing, now im told to replace the shifting modulator, i know its under the pan on trans.... any tricks or ideas fella's? i mean is my trans shot? what other options could be causing this to happen?

SOURCE: 2000 grand prix w/auto transmission wont shift into overdrive

some of the trannys has straps in them that sometimes needs to be tightened and that could be the cause of it

SOURCE: 2000 pontiac montana wont go into 4th gear

I would be interested in knowing if the thermostat is sticking open. Most Overdrives are prevented from engaging until the coolant temperature is over 177 degress F. Check you temp gauge...does it read Low? If so, change the t'stat, and see if that fixes your problem, or, if that does not help, get a complete transmission FLUSH, BEFORE you go out and get a rebuild. You just might save a ton of money.

SOURCE: trac off light is on shifts hard

i believe theres a small button on your shifter to push for trac off and on, there was on my 98 anyways...