I spoke with a local trans shop and while they told me what I was experiencing was not "normal" they did say that because of the frequency of it happening, the fact the trans had not thrown any codes, and because the trans had never limped it would be almost impossible to diagnose. It could be a loose wire, a sticking solenoid, or another half a dozen issues. Their suggestion was to wait until the problem was bad enough I could replicate it for them, or wait until I limped the trans.
Regarding the trans fluid levels, when checked they are in the high areas of the crosshatching on the trans dipstick annotated as "hot" and "cold" with the level appropriate for the temp of the transmission. Fluid checks are done on a level surface, and after shifting the trans through R D and finally P. Trans fluid is pinkish with a little bit of gold, probably close to time for a drain and fill.
Regarding the boost. I'm not surprised my reported levels are a little low, I also don't drive the truck very aggressively (it is an almost 4 ton vehicle after all). I've never done a 4wd launch, heck I've never done a proper 2wd launch under boost. Never even done a burnout or a donut. The boost levels I quoted are under heavy acceleration while passing for example. I'm sure my turbo it a bit worn after almost 200,000 miles and I expect to have to put a new one in sometime in the next 30k-50k. I've tested the system for leaks, and recently replaced the air filter. If you can describe a method for checking boost levels that would not involve me breaking laws excessively on city streets or putting excessive strain on the trans I can try and do it. I checked my edge insight and it's highest record boost value was 36lbs, although that has probably not been reset for over a year though. I reset it and I'll try and take the truck out tonight and see where I end up.
I apologize for not mentioning the tune, you are correct that is a very important bit of information that I left out. I could have sworn that I had added it to my sig when I was more active on these forums. I am well aware that no tune is "trans safe" and I am fully aware that the stock allison 6 speed is a bit of a weak link in the driveline. Since I am aware of that, I do my best to drive accordingly. I purchased tunes from Idaho Rob specifically because I was told his defueling between shifts was easier on the trans than other tunes. I drive my truck the way I imagine old people drive sports cars. Leisurely driving around 90% of the time with the other 10% being 3rd/4th gear roll on's on highway on ramps or occasional "brisk" starts from stop lights (with traction control on).
Regarding the different tunes. My available tunes are +0 HP towing, +40 hp towing, +90 hp economy, +120 hp "race" (never used), and Valet.
2009 Chevrolet 2500HD LTZ CCSB White 4x4
4" turbo back straight pipe
EFI live with Idaho Rob tunes (RIP)
Last edited by Epiclobotomy; 10-22-2019 at 01:29 PM.