Battery disconnect=PCM reset?

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I know I can clear error codes by disconecting the battery for about 30 seconds. What I am not sure about is that I heard it will cause the PCM to re learn the shift points right away rather than having to drive for 1,000 miles for it to do it automatic. Is this true? The sales manager at DC told me to do it before towing it would help. I have done this a few times but can't tell any difference.

Also is there a TSB to change the TC lock up speed, mine locks up faster than I care for under WOT (30mph 3rd / 45mph OD).

Thanks, Roger

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'98 12V 3500 Dually Std Cab, Auto, 3. 54, Banks Stinger Plus, Sun Coast TC. BD valve body, BD Pressureloc

 

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I did not notice any difference in shifting or a need for the pcm or transmission to re-learn shift points when I replaced both batteries about a year ago. Everything was down for about 30 minutes before the new batteries were intalled and hooked back up. Anyone have "tech info" on this?

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95 2500 SLT, clubcab, 2wd, longbed, a/t, 3. 54, 131K miles, "all the usual refinements"

 

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Originally posted by Roger Ledbetter:
... I heard it will cause the PCM to re learn the shift points right away rather than having to drive for 1,000 miles for it to do it automatic. Is this true? The sales manager at DC told me to do it before towing it would help. I have done this a few times but can't tell any difference.

Also is there a TSB to change the TC lock up speed, mine locks up faster than I care for under WOT (30mph 3rd / 45mph OD).

Like fortunate1, I've never noticed the transmission shift points changing after the PCM has been powered down. I believe the shift points are based entirely on throttle position, engine speed, gear and vehicle speed. On my truck, if I am accelerating lightly, the TC will lock up around 32/47 MPH. Under very slight power, I can get it to lock up at 25MPH in 3rd. Under hard acceleration, the TC will not lock up until much later (like 50 in 3rd, or 65 in OD).

If your truck *always* locks up at the normal minimum vehicle speed, you might first suspect the throttle position sensor; it might be indicating only the first 1/4 or 1/3 of throttle movement. Another indication of TPS error is if the transmission never 'kicks down' a gear at full throttle.

Fest3er

 

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Shift points are regulated by PCM from inputs from engine speed sensor, TPS, vehicle speed sensor. Fluid tempature sensor and fluid pressure sensor I believe have something to do with shifting also. (would have to look at manual for exact info.