881stGenRunner

my 88 v6 auto would not like to shift into OD when it was cold, now i have the ECT button switched from Norm to Power and now it is shifting into OD no problem. I dont know why this is happening, but i like it b/c now i can save soooo much more gas by cruising around at 2000rpm when going 55mph instead of 3000rpm at 55mph. Anyways, just thought this was interesting and if other people were having this sort of problem trying using it and maybe it will do the same. Peace.

dougtrd

keep in mind that while it may shift into OD more reliably now, the ECT button is designed similarly to the GM tow/haul mode. That means it automatically adjusts your shift points to maximize power/RPMs when it is engaged. This generally causes the computer to allow the engine to rev higher before upshifting, and to downshift earlier( similar to how you would shift a standard trans when hauling a load and/or climbing a steep hill). So even though it goes into overdrive and saves you gas on the highway, around town and for general driving you are actually lowering your MPG.

Doug

X-AWDriver

Some have reported either no change or even a little better mpg but that's probably the majority of highway driving. With my next tank I'm going to leave mine on and see what I get since do a good combo of city/highway. I have a feeling it'll be a little less.

881stGenRunner

well most of the driving i do goes through every gear then obviously goes into OD, but i am never in stop and go traffic and always able to hit the final gear. So in the long run this is helping me b/c it may use a little more when it accelerates longer, i am saving the gas in OD. I used to run 55mph at 3000rpm, now i can run it at 2000rpm. To me it is worth it.