I just bought a 06 envoy with the 4.2, just at 100k miles, I noticed it shifting hard just like my Grand Prix back in the day would but it had a line pressure control sensor that I replaced that fixed it, well I can’t find where or if the 4l60 has one, I also own a 05 trailblazer with 220k that shifts just fine, also with the envoy I noticed that there is no 4K rpm park limiter which I find odd. Only code is Evap and 02 sensor bank 1. Anybideas?