Hi, I have an MDrive transmission and am having a problem with my jake brake. When I put it at maximum, the majority of the time it does not downshift. It actually downshifts, but for half a second. We hear it downshift, it displays the lower gear but immediately returns to the gear it was. So I always have to downshift manually. I noticed that he did it especially at high speeds like 70 km/h and above. I was wondering if there is any programming to do to fix this. I got it new and it's always been like this. THANKS!
