This thread has got me wondering how my truck’s auto trans compensates its shifting algorithm for the 4WD transfer case selection, hi vs lo.
Your transmission has no way of knowing what the transfer case is doing, or even if it has one… Basically the only difference between a 4x4 trans and a RWD trans is the output shaft length and extension housing…
That being said, you might use more clutches in the drum(s), stronger/more planets, but that is more inline with it going behind a 4, 6 or 8 cylinder and or how much torque the trans can take…
You might adjust the modulator and kick down linkage a little due to the extra weight of the t-case and front diff…
Here is a basic VB repair/upgrade kit, and then a performance shift kit instructions for a C4 trans… Do you see anything about if it has a transfer case behind it or not?? The pic in the 2nd link shows a RWD, it is just a pic don’t overthink it…
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That definitely seems to be the case. The only interaction between the transmission and xfer case I know of is that the speedometer cable plugs into the xfer case rather then transmission. That wouldn’t make any difference in 4wd-hi, but it provides the correct speedometer display in 4wd-lo. The transmission’s shifting strategy still seems to work pretty good in 4wd-lo, which is what got me curious about this topic. I’ve always though the vehicle speed is the primary input to the transmission’s shifting strategy, but apparently it is more complicated.
The speedometer gear is located on the output shaft of whatever the driveshaft is attached to… 4wd hi vs low makes no difference to the speedo, it’s only there to drive the speedo cable to inform you of your speed…
On a non ECT the speedometer drive can be removed from the vehicle and the transmission will never know… meaning, it will not change the shifting patterns…
Showing my age perhaps but when I hear ECT, the first thing I think of is Engine Coolant Temperature sensor 
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Yeah, me too… lol
I just call them, that there fangled thing with all them there wires sticking out of it… 
That could describe just about anything now!
I suppose just calling it a Tranny is no longer acceptable.
And all the other good terms are taken; widget, thingamabob, whatchacallit, shifty mcshifter seems pretty cool but doesn’t exactly roll off the tongue.
Couldn’t just leave well enough alone. Those pesky electrical engineering types had to get their grubby little mitts on the transmission too…
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