[ZLRob]

Originally Posted by Patriot Motorsports USA

Do you or have you experienced harder shifts once your transmission is fully warmed up in the upper gears? I have a customer tracking a 2019 ZLE who has identified it to have the steel pan and I wonder if the difference between the 2019 to the 2020 updated A10s could have significant changes, which could be remedied by switching the valvebody & pan to the later model. Thoughts??

This is going to sound odd, but I have indeed experienced harsher shifts once the transmission was warmed up. After leveling things out properly back when I had the steel pan most of that subsided, however, some of it still existed. After dealing with some odd issues with throttle closure under high RPM circumstances during datalogging, what I ultimately found that was messing with shift quality and general drivability out of all things was my Soler ported throttle body. Which confirmed by messing with the throttle error percentage settings in the engine diagnostic side of things under the engine diagnostic tab (P2101). The code was also not setting when throwing me into reduced engine power mode despite going back to stock settings from the initially set 25% up and down parameters, which was a super odd side effect. I swapped back to OEM purely for test purposes and I found was that not only did I regain drivability ten fold (seriously EVERYTHING softened up and got proper), but I gained power output which was confirmed via a few different instances on datalog, particularly with the fact I went lean and MAF output, so now I'm going to stick to the OEM and call it a day.


If your customer is having issues and has an aftermarket TB, and the transmission fluid level is correct or the fluid is even brand new, he may want to take a good look into replacing his TB for test purposes to see if that helps things out.


Outside of that, the difference from the switchover between Gen 1 and Gen 2 pans didn't show me any overly outstanding difference in shift quality. I also would strongly not advise switching to a Gen 2 valve body unless it has been revisioned to the performance of, or overhauled by Next Gen Drivetrain because they have been documented to have big underlying issues that if left as is can cause major long term issues to the transmission. Quite notably the CDF drum, the converter, and if left as is long enough, to the actual clutches.


After putting in some good work on this set up via general miles and hard driving and experiencing great results out of it, he may very well be a solid candidate for trying this mod out. It didn't take much time or money to do outside of the cost of transmission fluid and the cost for materials and labor to get them welded up once obtained.