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Discussion Starter · #1 ·
I have a 2019 Canyon V6 with an 8L45. Had my trans fluid flushed on TSB at 86000km put about 30000 more on (117000km or 75000 miles) and now I'm having an issue where the truck is downshifting more frequently, it also will hold gears when cruising at about 50km/h - 60km/h at about 2000-2300rpm before it decides it wants to shift, it'll also kick in AFM and shift into V4 mode.

Tonight on my way home when the truck was sitting for a few hours it decided the first few shifts it would slip the clutches on shift would spike up in rpm to about 2200 in between shifts.

Any idea what could be causing this issue? I didn't have the dealer change the filter, could this be an oil pressure issue due to a more restrictive filter or an issue with something else. Am i dealing with a faulty TCM, I tried resetting with my trifecta tune, was good for about 5 miles then started acting the same way. Could i have a failed trans? Shifts are good and converter lock up is good ones it's all settled

Back story, I've been tuned with a trifecta tune since 65000km, and do some mile towing with a 14x7 tandem axle enclosed trailer carrying 2 snowmobiles, probably between 3500 and 4000 lbs, and have maybe towed about 2500-3000 km total. Mainly in the winter months so trans temps while towing rarely get over 135*F
 

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Discussion Starter · #2 ·
just had trifecta rebuild my tune so that i had the stock shifting and AFM disabled and all shifting issues seem to be better. they sent me a file that also has the trifecta shift mapping with AFM disabled, i might try and see if with their mapping things are the same or if it was AFM causing the problem but the truck shifts smoother with the stock shift patterns and lugs more then it used to before i had the truck tuned all together. i may just leave things this way
 

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It might be an issue with the trifecta tune program

you say you did not have the dealer change the filter, and could it e an oil pressure issue?

They changed the engine oi but you did not ahve them change the oil filter? If so, why not?
 

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Discussion Starter · #4 ·
It might be an issue with the trifecta tune program

you say you did not have the dealer change the filter, and could it e an oil pressure issue?

They changed the engine oi but you did not ahve them change the oil filter? If so, why not?
i meant the transmission filter and fluid

i don't think its an issue with the trifecta tune i went back to the stock tune and it did the same thing, would reset the TCM would shift smooth for about 10 miles then do the same thing again.

either way i'm happy that i disabled the AFM and have the stock shifting, shifts are alot smoother then with the trifecta mapping, you don't even feel the transmission shift, and with the increased torque it'll lug more
 
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