P0776 on 2008-2010 Saturn Vue: Causes, Symptoms, and Fixes for Pressure Control Solenoid 'B' Fault

What's Unique About the 2008-2010 Saturn Vue

For the 2008-2010 Saturn Vue equipped with the GM 6T70 or 6T75 6-speed automatic transmission (paired with V6 engines), P0776 is rarely just a bad solenoid. This code is a well-documented, classic symptom of a catastrophic internal failure: a broken 3-5-R (3rd-5th-Reverse) clutch wave plate. The original wave plates were not properly stress-relieved and were prone to fracturing. As the hardened steel plate breaks apart, metal fragments contaminate the entire transmission fluid system. This debris clogs the filter screens in the valve body and jams the delicate spools within the solenoids, causing them to stick, which is what ultimately triggers the P0776 code. Simply replacing the solenoid is a temporary fix at best, as the root cause—a disintegrating mechanical part—remains.

Symptoms You May Notice

• Complete loss of Reverse gear
• Harsh, banging, or delayed shifts, especially into 3rd and 5th gear
• Transmission slipping, where the engine revs up but the vehicle doesn't accelerate properly
• Inability to shift into higher gears, with the transmission stuck in 'limp mode' (often 2nd or 3rd gear)
• Illuminated Check Engine Light
• Transmission goes into limp mode but may operate normally when cold, with symptoms appearing or worsening as the fluid warms up.

Most Likely Causes

1. Broken 3-5-R Clutch Wave Plate 🔴 High Probability The original wave plate in the early 6T70/6T75 transmissions was a known weak point due to a design flaw where it wasn't properly stress-relieved, making it prone to fracturing over time. This is a widely recognized issue covered by multiple GM Technical Service Bulletins (TSBs).
   How to confirm: A definitive diagnosis requires a transmission specialist. Initial signs include finding significant metallic debris (often looking like metal shavings or chunks) in the transmission fluid and pan. Confirmation requires transmission disassembly to visually inspect the 3-5-R clutch pack.
   Typical fix: The transmission must be removed, completely disassembled, and rebuilt. This involves replacing the broken wave plate with an updated, stronger design (Part No. 24254103), replacing all other damaged components (like clutches, seals, and potentially the torque converter), and thoroughly cleaning all metal debris from the case, valve body, and cooler lines.
   Est. part cost: $500-$1000 for a full rebuild kit
2. Contaminated Transmission Fluid and Clogged Filter 🟡 Medium Probability → Shop Transmission Assembly This is a direct result of the wave plate failure. The fluid becomes saturated with metallic debris, which clogs the internal filter plate and the main filter, starving the transmission of clean, properly pressurized fluid.
   How to confirm: Check the transmission fluid level and condition. If the fluid is dark, burnt-smelling, and has visible metallic particles, it confirms severe internal wear.
   Typical fix: This is fixed as part of the transmission rebuild. A simple fluid and filter change will not solve the problem and is a waste of money if the underlying mechanical failure is not addressed.
   Est. part cost: $50-$100 for fluid and filter
3. Faulty Pressure Control Solenoid 'B' or Solenoid Pack ⚪ Low Probability → Shop Transmission Valve Body The solenoid itself is not typically the primary failure. It fails or gets stuck because metal debris from the broken wave plate has jammed its internal valve. Replacing it without addressing the debris source will lead to a repeat failure.
   How to confirm: A technician can command the solenoid on and off with a high-end scan tool to check its response. However, even if the solenoid tests bad, it is almost certainly a symptom of the larger wave plate issue on this platform.
   Typical fix: Replacement of the solenoid pack (part of the TEHCM), which is located inside the transmission. This should only be done after confirming the wave plate is intact, which is highly unlikely on a Vue with this code and symptoms.
   Est. part cost: $150-$300

Rare But Worth Checking

• Faulty Transmission Control Module (TCM): → Shop Transmission Assembly The TCM (also called TEHCM) is integrated with the valve body and solenoids inside the transmission. While a faulty TCM can cause solenoid codes, it is very rare compared to the mechanical wave plate failure on this platform. This should only be considered after all mechanical possibilities have been ruled out.
• Wiring Harness Damage: Damage to the wiring between the main ECU and the transmission could cause this code, but it's uncommon. This would typically be from physical damage or corrosion, and would likely present with multiple other communication codes.

Diagnosis Steps

1. Scan the vehicle for all stored trouble codes to see if other transmission codes are present, which is common with this failure.
2. Check the transmission fluid level and condition. Look for a low level, burnt smell, or visible metallic particles on the dipstick or a cloth. This is a strong indicator of internal damage.
3. Given the high probability of wave plate failure on this specific vehicle, consult a transmission specialist immediately. This is not a typical DIY diagnosis.
4. The specialist will likely drop the transmission pan to inspect for large amounts of metal debris, which confirms a major internal failure.
5. If significant debris is found, the only correct procedure is to remove and disassemble the transmission for a full inspection and rebuild, or replace it with a remanufactured unit.

Parts You'll Likely Need

• Transmission Rebuild Kit (including updated wave plate) — This is required to fix the root cause, the broken 3-5-R wave plate, and replace other worn components like clutches and seals during the mandatory rebuild.
  Trusted brands: ACDelco, Transtar, Sonnax
  OEM price range: $600-$1000
  Aftermarket price range: $400-$700
• Updated 3-5-R Clutch Wave Plate (OEM #24254103) — This is the specific, updated part that corrects the original design flaw. It must be replaced during any rebuild.
  Trusted brands: ACDelco
  OEM price range: $30-$50
  Aftermarket price range: $20-$40
• Remanufactured Transmission — For many owners, replacing the entire transmission with a remanufactured unit (which has the updated parts already installed) is a more time-efficient and reliable option than rebuilding the original.
  Trusted brands: Jasper, Moveras, ACDelco
  OEM price range: $3500-$5000
  Aftermarket price range: $2500-$4000
• Transmission Fluid (DEXRON-VI) — The transmission will require a full fill of 9-10 quarts of new, clean fluid after a rebuild or replacement.
  Trusted brands: ACDelco, Valvoline, Castrol
  OEM price range: $10-$15 per quart
  Aftermarket price range: $8-$12 per quart

Related Codes That Often Appear With This One

• P0777 — This code for 'Pressure Control Solenoid 'B' Stuck On' is the counterpart to P0776 and can be triggered by the same debris-related issue.
• P0716, P0717, P2714, P2715 — These are all transmission-related codes (Input Speed Sensor, other solenoids) 🎬 Watch: See how a broken wave plate triggers these specific codes. that can be triggered by the same root cause: the broken 3-5-R wave plate causing widespread hydraulic and electrical faults within the transmission due to metal debris. NHTSA ODI #10860560 confirms that these codes frequently appear together on Saturn Vue vehicles with the 6-speed automatic transmission.

Technical Service Bulletins (TSBs) & Recalls

• 09-07-30-012F: No Reverse, 3rd or 5th, Check Engine Light Illuminated, DTC P0776 (Replace 3-5 Reverse Clutch Plate (Waved)). This TSB explicitly identifies the broken wave plate as the cause.
• 14404B: Special Coverage Adjustment - No 3rd, 5th, or Reverse gears due to broken 3-5-R wave plate.

Platform-Specific Known Issues

• A Technical Service Bulletin (TSB 09-07-30-012F) was issued by GM for the 6T70/75 transmission concerning this exact issue: no reverse and 3rd/5th gear shift problems accompanied by code P0776, caused by a broken 3-5-R wave plate.
• GM also issued a Special Coverage Adjustment (14404B) extending the warranty on this specific failure to 10 years or 120,000 miles. This coverage has since expired for all affected vehicles.
• NHTSA ODI #10631310 highlights owner frustration regarding the lack of a formal recall for these transmission faults, noting the potential safety risks when the transmission fails.

Mechanic-Grade Diagnostic Values

• Pressure Control Solenoid (PWM) Resistance — expected: 4-7 ohms. Failure: A reading outside this range indicates a faulty solenoid coil. This test is performed on the TEHCM with it removed from the vehicle.
• Shift Solenoid (On/Off) Resistance — expected: 20-40 ohms. Failure: A reading outside this range suggests a bad shift solenoid. This test is performed on the TEHCM with it removed from the vehicle.
• Line Pressure at Idle (in Park) — expected: 50-80 PSI (345-550 kPa). Failure: Significantly lower pressure can indicate a worn pump, major leaks, or clogged filter. Higher pressure could indicate a stuck regulator valve.
• Line Pressure Stall Test (in Drive) — expected: 270-300 PSI (1860-2070 kPa). Failure: Inability to reach this pressure under load points to severe internal hydraulic issues, often related to the pump or massive leaks from the wave plate failure.

Scan Tool Commands That Help

• GM Tech 2 / GDS2: Solenoid Performance Test — This function allows a technician to command each solenoid ON and OFF individually to check for response. For P0776, the focus is on PC Solenoid 2 (3-5-R). A lack of response confirms a problem, but on this vehicle, it's likely caused by debris, not just a bad solenoid.
• GM Tech 2 / GDS2: Transmission Cleaning Procedure — This automated process cycles all solenoids while the system is pressurized to dislodge minor debris. While GM recommends it before replacing a TEHCM, it is NOT a fix for the P0776 wave plate issue, as the amount of metal debris is too great to be cleared by this function.
• GM Tech 2 / GDS2: Fast Learn / Adaptive Learn Reset — This procedure MUST be performed after a transmission rebuild or replacement. It resets the adaptive pressure settings, allowing the TCM to learn the characteristics of the new or rebuilt components. Failure to perform this step will result in poor shift quality even after a successful mechanical repair.

Real Owner Repair Stories

• SaturnFans.com Forum (2008 Saturn VUE, 3.6L V6, 92,000 miles) — Loss of 3rd, 5th, and Reverse gears. Check Engine Light on with code P0776.
  ❌ Tried (didn't work) The owner first suspected a simple solenoid issue before learning about the wave plate problem.
  ✅ What actually fixed it The vehicle was covered under GM's Special Coverage Adjustment 14404. A GM dealership confirmed the diagnosis and performed the transmission repair, which involves replacing the broken 3-5-R wave plate, at no charge to the customer. This confirms the wave plate as the direct cause of the failure and the code.
• NHTSA ODI #10568563 — An owner reported a sudden loss of reverse gear. A transmission specialist identified codes P0776 (PCSB Stuck Off) and P2715 (PCS4 Stuck On), noting the failure occurred shortly after the powertrain warranty had expired.

OEM Part Supersession History

• Unknown (Original design wave plate) → 24254103 — The original 3-5-R wave plate was prone to fracturing. The updated part is made from stress-relieved, hardened steel to prevent this failure.

Model Year Variations Within This Range

• 2008-2009: When rebuilding the transmission, the control valve channel upper plate must be inspected. For 2007-2008 applications, the plate must have a specific slot. Installing a plate without this slot can result in setting DTCs after the repair.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Premature Timing Chain Stretch (3.6L V6) 🔴 High — Common around 100,000 miles, often accelerated by infrequent oil changes. Can cause engine damage if not addressed. (Ref: Multiple TSBs exist for related DTCs (e.g., P0017), but no universal recall.)
• Power Steering Failure (Electric/Hydraulic) 🟠 Medium — Reports of sudden loss of power steering assist. Can be caused by failing electric assist motors, faulty alternators, or leaking hydraulic lines on some models. (Ref: NHTSA Campaign 08V470000 for leaking power steering lines on some 2008-2009 models.)
• Faulty Gas Cap Causing Check Engine Light 🟡 Low — A very common and simple issue where a worn or loose gas cap seal triggers an EVAP system code and illuminates the check engine light.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used transmission from a junkyard is a very high-risk option for this repair. Since the wave plate failure is a design defect tied to the model year, a used unit from another 2008-2010 Vue (or similar GM vehicle) is highly likely to have the same defect and either has failed already or will fail soon. It only makes sense if the donor vehicle is a later model (2011+) where the issue was corrected and has documented low mileage.

Donor-vehicle mileage cap: roughly under 60000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• Check the VIN of the donor vehicle to confirm it's a 2011 or newer model.
• Ask for a video of the donor vehicle running and shifting through gears, if possible.
• Pull the dipstick on the donor transmission; if the fluid is dark, burnt, or contains any metallic sheen, walk away.
• Get a warranty from the salvage yard, even if it's only 30-90 days, to protect against an immediate failure.

OEM-only on this vehicle (don't cheap out):

• Updated 3-5-R Clutch Wave Plate (Part No. 24254103). Using a non-OEM or old-stock part guarantees a repeat failure.
• Transmission Control Module (TEHCM). While aftermarket TEHCMs exist, they can have compatibility issues. A new or remanufactured OEM unit is the safest bet.

Aftermarket brands forum-validated for this vehicle:

• Sonnax: For valve body repair kits ('Zip Kits'), oversized valves, and other professional rebuild components. They are the industry standard for addressing wear-and-tear issues beyond the wave plate.
• Transtar / Transtar-branded rebuild kits.
• Jasper / Moveras: For complete remanufactured transmissions that come with a warranty and have all updates installed.

Brands owners have reported issues with on this vehicle:

• No-name, unbranded solenoid packs or rebuild kits from online marketplaces. The quality control is non-existent, and for a labor-intensive job like a transmission rebuild, using low-quality internal parts is a recipe for disaster.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Documented NHTSA Reports

Related OBD-II Codes

• P0700 — Transmission Control System Malfunction. This is a generic informational code that is set by the Engine Control Module (ECM) whenever the Transmission Control Module (TCM) stores a specific fault code like P0776. It's a flag indicating a transmission problem exists.
• P0777 — Pressure Control Solenoid 'B' Stuck On. This is a companion code to P0776. The same metal debris from the broken wave plate that causes the solenoid to stick off (P0776) can also cause it to jam in the 'on' position.
• P0741 — Torque Converter Clutch Circuit Performance or Stuck Off. The widespread contamination of transmission fluid with metal debris from the wave plate failure often damages other components, including the torque converter clutch and its solenoid, leading to this code.
• P0751 — Shift Solenoid 'A' Performance/Stuck Off. The root cause of P0776 on the Vue—metal debris circulating in the fluid—is not isolated to a single solenoid. It's common for other shift solenoids in the valve body to become clogged, triggering their own performance codes.
• P0017 — Crankshaft/Camshaft Position Correlation. While an engine code, this is another very common high-cost repair on the 3.6L V6 engine used in the Vue, typically caused by stretched timing chains. It can occur independently but is a frequent issue for owners of this specific powertrain.

Frequently Asked Questions