P0756 on GMC: How to Diagnose & Fix
Shift Solenoid B Performance/Stuck Off
1 GMC model · 1 documented issue · $150-$2,800 repair
P0756 on GMC by model: symptoms, diagnosis and fix
The 2010-2017 Terrain uses the GM 6T40 (2.4L) and 6T45 (V6) 6-speed automatic transmissions, both of which suffer from torque converter shudder, harsh shifts, and solenoid failures. The shudder occurs at light throttle between 30-50 mph when the torque converter clutch locks up. Solenoid pack wear causes P0756, P0751, and P0776 transmission fault codes. The transmission is sensitive to fluid condition — the 6T40/6T45 was originally filled with Dexron VI, but older Dexron VI degrades faster than newer formulations.
Common Symptoms
- Shudder at light throttle 30-50 mph
- Harsh 1-2 or 2-3 upshift
- Hesitation or lurch when pulling away from a stop
- Transmission fault codes P0756, P0751, P0776
- Check engine light
- Delayed engagement from Park to Drive when hot
How to Fix
Full fluid exchange with Dexron VI (ACDelco 10-9243 or equivalent). TCM calibration update. Solenoid pack replacement (GM 24272814) if codes present. Valve body replacement for internal failures. Fluid service every 40,000 miles recommended for stop-and-go use.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Dexron VI full-synthetic automatic transmission fluidOEMACDelco 10-9243 (GM 88865549)Cross-refValvoline DEXRON VI ATF 822405, Mobil 1 Synthetic ATF Dexron VI 112980, Castrol Transmax DEXRON-VI 03520C$8–$15
Dexron VI is required — do NOT substitute Dexron III or a universal/multi-vehicle ATF, as the friction
- Control solenoid valve assembly (valve body + solenoids + TEHCM) — 2.4L, 2012-2013OEM24041960$600–$960
THIS is the part that actually fixes P0751/P0756/P0776 on the 6T40/6T45. GM does not sell the individual shift/pressure-control solenoids for this transmission as a serviceable part — the solenoids are integrated into the TEHCM/valve bod…
- Control solenoid valve assembly (valve body + solenoids + TEHCM) — 2.4L, 2014-2017OEM24041961$598–$915
Same function as 24041960 but the correct number for the later 2.4L Terrain — this is the year split, so do not cross-order between them.
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Sources for this issue (1)
P0756 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0756 mean on a GMC?
P0756 stands for "Shift Solenoid B Performance/Stuck Off." This code means the transmission control module commanded Shift Solenoid B (sometimes called Shift Solenoid 2) to operate, but the transmission did not respond as expected, with the solenoid behaving as if it is stuck in the 'off' position. Shift solenoids are electrically controlled valves that route transmission fluid pressure to engage the correct gears, so a stuck or weak solenoid can cause harsh, delayed, or missed shifts. The computer sets this code when the actual gear ratio or shift timing does not match what it commanded. It generally points to a hydraulic or electrical performance problem inside the automatic transmission rather than a simple wiring short. On GMC it is documented across 1 model: Terrain.
What are the most common causes of P0756?
The most common causes of P0756 are: Stuck or failed Shift Solenoid B, Low, dirty, or degraded transmission fluid, Clogged solenoid or valve body passages from debris, Worn or sticking valve body components, Wiring or connector fault to the solenoid, Internal transmission wear or mechanical damage, Faulty transmission control module. The specific cause varies by vehicle.
How much does it cost to fix P0756 on a GMC?
Published repair estimates on GMC range from $150 to $2,800 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0756 on a different make?
View P0756 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.