[Slurpee]

Originally Posted by ZLRob

It's just a hard shift. Like as soon as you shift down into 3rd gear or up into 4th it just feels like a jolt and it's done, very common on these transmissions but interestingly enough I noticed when I initially put in 6 quarts into it I noticed that it shifted all very softly. However, I also know that this transmission changes the way it performs over time so anything that's different it will adjust to and potentially perform poorly over (over a long term perspective). I can confirm that based on the way my old set up was overfilled and it absolutely hated it but performed well with it for a very long time despite that until the fluid started getting a little dirty. The change in shifting I felt was more likely than not a temporary false positive.

I have 1 more 2 day event on this fluid and then I think I am going back to my original pan to see if that changes anything. I wonder if the regular ZL1 is specifically calibrated for the longer stand pipe. Which may support why I had no hard shifts at WGI with the fluid expansion at 95F.

Mine took 6.25 qt, with spillage.

The hard shifting has also never happened on the street. The dealer was unable to replicate (of course)

[ZLRob]

Originally Posted by Slurpee

I have 1 more 2 day event on this fluid and then I think I am going back to my original pan to see if that changes anything. I wonder if the regular ZL1 is specifically calibrated for the longer stand pipe. Which may support why I had no hard shifts at WGI with the fluid expansion at 95F.

I had hard shifts with the standard pan anyways. It's been pretty well noted that the A10 shifts hard between 3-4 and 4-3 gears because the ratio is so close to each other. I also believe that it may be a learning behavior characteristic which is not programmable in the controller itself because if you do a reset on the learning parameters the trans will shift soft for some time but then will go back to shifting hard which you cannot tune out.