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Posted

15 2500 gas motor with. Since I did the black bear tune about 2 years ago I've noticed that anytime I drive longer than an hour the converter locks up in 4th or 5th and I can't get it out. I even trying to change it manually nothing happens. If I shut the truck off and restart the truck she then will start the shift normal again. I had pedal commander on the truck and BlackBear told me that that's what was causing my issue I remove that and I am still having the issue. What do you think can cause this and why when i tell the truck to go Into 6th gear while on the highway it doesn't. The 4:88 gears were done this year and this has been a on going issue for 2 years. 8b21cdd08928346e467312b27eb9fe5f.jpg

 

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Posted

That's a new one to me.

 

I wouldn't say it's a converter issue but something wrong with the programming and it not wanting to shift gears. The converter will lock if it's set to lock in whatever gears it's told to. I always change the lock up settings and what gears/speeds it's allowed to do so.

 

Not being able to see how blackbears setups the calibration I can't really say why it's not upshifting to 6th gear.

Posted (edited)

i also had issues with my "sprint booster" throttle enhancer, truck was idling high and throwing a code, for a ground short. take that stuff off immediatly.  have the dealer or trans shop do a trans relearn with the scan tool

Edited by flyingfool
Posted
i also had issues with my "sprint booster" throttle enhancer, truck was idling high and throwing a code, for a ground short. take that stuff off immediatly.  have the dealer or trans shop do a trans relearn ....
I have a trans tune. This started prior to pedal commander. Started after blackbear trans install. I no longer have throttle controller installed.

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Posted

if its an 8 speed, guys have reported those improve dramatically with a dealer fluid flush, but i think the dealer is just doing the "Re-learn procedure" , there is also a procedure that cycles and bleeds out any airlocks in the solenoids and clutch packs after overhauling.  find a good trans shop with a snap on scan tool that can do these or go to dealer and ask the mechanics if they can do it.

Posted

6l90, i just did a fluid and filter change. Hoping that would have fixed it. A friend said its a poss program issue cause it resets after i turn the truco off.

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Posted

Scan for trouble codes. When certain fault codes are current the tcm won't allow upshifts to certain gears.Po741 is one example. The six speed in your truck has been known to have convertor failure issues.How did the fluid and filter look when you had the pan down? Any metal on the magnet.

Posted
install the stock trans file, then relearn, then retune it from a fresh base line
Emailed blackbear for a updated stock tune cause i did 4:88 gears. Prob take another month for the update

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Posted

better off getting HPtuners.. the tune repository should have the stock files, and you can adjust for gear change in 5 minutes yourself

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