The Proton Saga FLX CVT (Continuously Variable Transmission) gearbox is a type of automatic transmission introduced by Proton in the Saga FLX variant, which was launched in 2011 as an improvement over the original Saga FL. Here’s a detailed description of the gearbox and its features:

1. Type of Gearbox

• CVT (Continuously Variable Transmission)
  Unlike traditional automatic gearboxes that use fixed gear ratios, a CVT provides a seamless range of gear ratios. This allows the engine to operate at its most efficient RPM for a range of vehicle speeds.

2. Supplier and Model

• The CVT used in the Proton Saga FLX is the Punch Powertrain VT2+ CVT.
  
• Punch Powertrain, a Belgian company, supplied the gearbox.
• The VT2+ is a lightweight, fuel-efficient CVT designed for small passenger cars.
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3. Key Features

• Fuel Efficiency:
  
• Offers better fuel economy compared to the previous 4-speed automatic gearbox in the Saga FL.
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• Smoother Acceleration:
  
• No gear shifting means a smoother ride without the ''kick'' of traditional gear changes.
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• Low-Speed Creep Functionality:
  
• Provides a similar ''creep'' behavior to traditional autos when releasing the brake—useful for traffic jams.
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• Simulated Gear Feel:
  
• Some tuning was done to simulate gear steps to make the driving feel more natural for those used to regular autos.
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4. Performance

• Paired with the 1.3-liter CamPro IAFM+ engine in the Saga FLX.
• The CVT helps optimize power delivery for urban driving, though it may feel less responsive for aggressive acceleration.

5. Common Issues (Reported by Users)

• Rubber Band Effect: Engine revs increase without a proportional increase in speed—common to many early CVTs.
• Juddering at Low Speeds: Some users reported slight shuddering during slow acceleration, typically due to belt/cone wear or software calibration.
• Transmission Overheating: If not well maintained or when used in heavy traffic for long periods without cooling.
• Maintenance Sensitivity: Requires CVT-specific fluid and proper service intervals to avoid issues.

6. Maintenance Tips

• Always use CVT-approved transmission fluid (e.g., Punch CVT Fluid or equivalent).
• Follow service intervals strictly (typically every 40,000–60,000 km for fluid changes).
• Avoid aggressive driving to extend the lifespan of the CVT.

Summary

The Proton Saga FLX CVT gearbox was a modern addition aimed at improving drivability and efficiency over the older 4-speed automatic. While it delivers on smoother and more economical driving, it requires regular maintenance and careful driving habits to ensure long-term reliability.