Un related but I have speed bumps in my neighborhood. When I slow down and coast over one, sometimes when I hit the gas, it goes into neutral for a second, revs and then dumps into 1st. Still under warranty, I don't know if it is an issue. All stock tune.

 

No Chief, it does it when i have it pinned down to the floor at WOT. but to me it honestly feels like the oil is the issue. reason i say this is because when i step on it from 0 it has alot more time goin forward and making all the oil go to the back of the tranny.. and when i step on it from around 28mph it is alot less time goin forward before the shift to 2nd so all the oil does doesnt have enough time to go all to the back i would think. thats my theory but im just saying.lol i dunno. maybe it is something to do with rev limiter and or torque management.. but ill check that out when ever charlie has time to mess with the settings....

But my question now is what would happen if i add fluid to the tranny? say a 1/2 quart or so.. even though the level is right where it should be at?

mine has done that before a couple of times, i think its normal

 

i dont think ive ever had this particular issue, but every other issue ive had with the 6L is something that always seems to change or go away when i play with the tune... FWIW

 

Torque management and throttle position is kind of hokey on my truck below 20mph (L76/6L80e). I have no problem from a dig, as long as wheelspin is done before the truck gets to ~4500rpm. If I still have wheelspin as I near the shiftpoint it falls flat on its face when getting into second.

A harsh tip-in at around the shift point causes it to poop itself also. It seems like it's busy trying to find a prime number with 10 billion digits or something.

And lastly, if I manage to break traction near a shiftpoint it'll hit fuel cut-off and it feels like I threw out a parachute.

 

^^ yea very true, i know exactly how all of that feels as i too have experienced all of that.. but this is something different.. but like most of you guys say it is most likely something that needs tweakin in the tune.. but i have yet to make time to set something up with charlie to make slight changes in the tune and see what outcome i get out of it.

 

I had this problem when I had the predator programmer and custom tune from a predator dealer. At first is was terrible felt like I would turn the truck off the start it again between the 1 - 2 shift. I then checked the predator custom tune and found the 1 - 2 shift was at 36mph but the Shift RPM was still at 5200rpms IIRC. I changed the shift rpm to 5800 and it shifted much better and would seldomly "cut out" at the shift point.

About 6 months ago I had my truck tuned with HPT and around the same time had a vette servo installed. 1 - 2 shift is about perfect now and most of the time it will "chirp" the tires. I did have all Torque Management turned off when it was tuned with HPT. I'm just keeping my fingers crossed that I'll have a new truck before I have trans problems.

A GMC Mechanic and tuner told that this issue is mainly caused by Torque Management but can also be caused by something with the ABS and wheel speed sensors. WOT, truck is spinning, speed-o-meter and tac jump up and show truck is moving faster than it is actually going. So basically the PCM gets confused and doesn't know when to shift. Just passing on what I was told....hope this helps.

 

my truck does the same think... sounds like shifting a standard... like the throttle blade completely closes for a sec... i havent pin pointed when it does it either.. for now seems kind of random... idk.. my tuner and i are due for some data logging so ill se what he can come up with...

 

Nice Avatar CharlyNali6.2

 

Thanks guys ill keep all of this in mind when i go see wheatly. im supposed to meet with him today hopefully nothing comes up...although i havent noticed it doin the problem so much lately.. i just hope it does it when hes on the truck so he can see what im talkin bout

thanks silverbirch i like urs too!!!!
well need to set up a polish billet wheels day! lol

 

so did charlie fix this issue?