Just changed the trans oil on the Allison. My truck has 31000 miles on it. The trans fluid looks like a very dark silver metalflake paint. There is no pink at all. There were no problems to date except for an occational shutter when downshifting under hard braking. I use a Superchips tuner set on Level 1 and tow a trailer weighting in at 8600 pounds. There are no codes nothing. Any advise? I have an appointment with the dealer Friday. The truck goes out of warranty next month.