Bought the L about a month ago from a guy on here. Overall it runs and drives great, but around 35-40mph, if I'm just cruising at that speed, the tranny will shift gears from 3rd to 4th and back to 3rd within 1/4th of a second. It does it pretty often if I'm driving in that situation. Other than that it works fine. The truck has about 43K on it now. Has anyone ever had this happen before? I'm wondering if I should change the fluid and see if it goes away, but I wanted you guy's opinions before I start throwing money at it. It doesn't have an aftermarket valve body, and the tune did not modify anything within the tranny from what the tuner has told me. Thanks for your help.
