6 speed trans is acting up

Rob Tavarus · September 29, 2016

I bought my 2016 back in March of this year. It came with a dealer installed lift and 35" Toyo MT's. Needless to say, with the poor throttle response and oversized tires the truck became somewhat miserable to drive. I did some research and ended up getting Black Bear EFI Live tunes which I had data logged prior to receiving. Everything was fine, the throttle response was much better and the transmission seemed like it was more responsive and in the right gear that it needed to be. Over a month or so, I noticed that it would flare shift into OD1(5th) or OD2(6th) when I was under 50 mph. If it made the same shift over 50 it was completely fine. I immediately notified Black Bear and sent them a data log while replicating the issue. Justin said the pressure seemed a bit low and sent me another trans tune. I loaded this tune and it seemed to be about the same, maybe even a little worse, so I said screw it and dealt with it. Now about 2 months later, the last two days, I'm developing a flare on the 1-2 shift which is further amplified to the clueless bystander by the Flowmaster 40. It only seems to do it on the way home from work and not early in the morning on the way in. And the worst part is I have been extremely easy on the truck, driving like a grandpa. I'm wondering what I should do here or if there is a known issue with the valve bodies or anything I can look into. Worst case, it goes to the dealer for warranty work after I flash the stock tuning back on it. With my luck they won't be able to replicate the issue. What do you guys/gals think?

HondaHawkGT · September 29, 2016

I'm not an expert on the 6L80 but I know Sonnax makes a ton of affordable upgrades. They sell a zip kit that's supposed to address flaring/low pressure issues.

http://www.sonnax.com/parts/3505-zip-kit

07Softail · September 30, 2016

As stated above Sonnax has some upgrades that I have bought like the Zipkit, Line booster, Slide Spring, and 2 apply pistons and a laminate replacement kit (in case they are torn). Have not yet installed but it won't be much longer just dreading dropping the damn tranny to do it is the bigger issue for me installing the upgrades is the easy part.

RT