P0741 on Cadillac

The CT5 uses GM's 10-speed automatic (10L80) that can exhibit harsh shifts, delayed engagement, and shift hunting, particularly when the adaptive learning resets. The 10-speed has very complex shift logic and can take 500+ miles to fully adapt to a driver's pattern after a battery disconnect, TCM update, or reset. Some CT5 owners report persistent shift quality issues even after adaptation. The CT5-V and CT5-V Blackwing have refined calibrations but can still exhibit occasional harsh shifts.

The CT5 pairs both its 2.0L turbo and 3.0L twin-turbo engines with a GM 10-speed automatic (10L80/10L90), which can develop a torque converter clutch (TCC) shudder felt as a vibration or 'rumble-strip' shake, typically at light throttle and steady cruise (roughly 25-55 mph) when the converter clutch is applying. The accepted root cause is TCC friction-material shedding and fluid contamination degrading TCC apply. GM issued TSB 22-NA-080 covering 10L80/10L90 TCC shudder (added July 2022, later revised to add newer model years). This is distinct from the 10L80/10L90 control-valve-wear recall and from harsh-shift/solenoid codes. Verified: TSB 22-NA-080 exists and covers this transmission family; CT5 use of the 10-speed with both engines is confirmed; CT5/V-Series owner shudder reports are corroborated on forums.

The 5th generation Escalade (2021+) uses the GM 10L80 10-speed automatic transmission. While improved over the 8L90, some owners report harsh shifting, shudder at light throttle, and delayed shifts. The 10-speed has numerous clutch packs and a complex valve body with frequent adaptive learning resets needed. Some units develop torque converter shudder similar to the 8L90 issue. GM has released multiple TCM software updates to address shift quality. The issue is less prevalent than the 8L90 but still documented.

The 2015-2020 Escalade uses the GM 8L90 8-speed automatic transmission that suffers from a widespread torque converter shudder issue. The shudder typically occurs at light throttle between 25-50 mph and feels like driving over rumble strips. The root cause is the torque converter clutch wearing prematurely, contaminating the transmission fluid with clutch material. GM extended the warranty and released updated torque converters and fluid, but many owners still experience the issue after the fix. This was the subject of a class action lawsuit.

The GM 6L50 6-speed automatic transmission in V6-equipped STS models is prone to overheating and developing harsh shift quality. The transmission fluid cooler is undersized for the vehicle weight, and the valve body solenoids degrade from heat cycling. Fluid darkens rapidly, and shift quality deteriorates with delayed or slipping 3-4 and 5-6 upshifts. The torque converter clutch also fails prematurely from heat damage.

The Cadillac XT5 uses an 8-speed (2017-2019) or 9-speed (2020+) automatic transmission. The 8-speed shares the torque converter shudder issue with other GM 8-speed vehicles. The 9-speed (GM 9T50/9T65) can have harsh shifts, delayed engagement, and shift hunting. Both transmissions have been subject to multiple software calibration updates from GM. The 9-speed is particularly sensitive to fluid condition and requires proper Dexron HP fluid.

XTS models with the 6T70/6T75 6-speed automatic exhibit a torque-converter-clutch (TCC) shudder felt as a vibration/'driving over rumble strips' sensation under light acceleration, typically 1000-1800 RPM in 4th/5th/6th gear, and a launch shudder from a stop. GM acknowledged the launch/upshift-downshift shudder in service bulletins covering XTS through 2019 with 6T70/6T75/6T80 transmissions; degraded transmission fluid that no longer holds the TCC friction material is the leading cause. A separate TSB (13120A) addresses a TCC solenoid sticking on debris.