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Non-Domestic Product: No

Custom Bundle: No

Fitment Type: Direct Replacement

Items Included: See picture

Manufacturer Part Number: HP-4L80E-01

Vintage Part: No

Modified Item: No

Transmission Type: Automatic

Brand: Sonnax

Type: Rebuild Kit

Manufacturer Warranty: Unspecified Length

Surface Finish: New

Universal Fitment: Yes

Performance Part: Yes

Sonnax Performance Pack HP-4L80E-01

Fits 1991-On 4L80E & 4L85E Models

Sonnax Performance Pack HP-4L80E-01 upgrades GM 4L80-E and 4L85-E transmissions for maximum performance and durability in work/sport vehicles. Innovative components work together to precisely recalibrate pressures and shift accumulation, delivering firmer shifts under load without sacrificing low-speed drivability. To target common wear areas in the transmission, the kit includes many improved parts to repair damage, prevent future wear and improve reliability.

  • Recalibrated shift accumulation, with tunability for great, heavy-duty shifts
  • Improved pump components minimize leaks, plus maintain pressure and lube under demanding use
  • The only way to eliminate TCC PWM function without over-pressurizing the converter
  • Includes internal parts for setup and to prevent common failures
  • Line Pressure Booster Kit
  • Lube Regulated Pressure Regulator Valve
  • TCC Pressure Limiter Valve, Spring & Plug
  • AFL Filter End Plug & O-Ring Kit
  • Direct Clutch Dual Feed Plug
  • Direct Clutch Dual Feed Aluminum Plugs (3) 2 Extra
  • 1-2, 2-3 & 3-4 Accumulator Piston Springs (3)
  • Checkballs (8)
  • Twist Drill .062"
  • Twist Drill .086"
  • Heavy Duty Case Bushing & Bearing Kit
  • Direct Housing Support Ring & Seal
  • Heavy Duty Intermediate Piston Spring Retainer Plate
  • Case Saver Retainer
  • Heavy Duty Clutch Retaining Ring Intermediate Clutch
  • Accumulator Valve Springs & Adjustable End Plug 2 Springs
  • Heavy Duty Direct Piston Return Springs (8)
  • Forward Clutch Hub Front Washer .078"
  • Reverse Servo Spacer Kit

Installation recommendation: Experienced technician
Transmission removal necessary: YES

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