Transmission Parts

Browse all Sonnax transmission parts here, or use the filters below to find just what you are looking for.

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4L60-E, 4L65-E, 4L70-E Boost Valve Kit 77898E-14K

4L60-E • 4L65-E • 4L70-E

Boost Valve Kit 77898E-14K

Late style, .421" dia. OE ratio, O-ring style

    Helps cure:
  • 3-4 Clutch failure
  • 2-4 Band failure
  • Low line rise
  • Poor shift quality
4L60-E, 4L65-E, 4L70-E Boost Valve Kit 77898E-16K

4L60-E • 4L65-E • 4L70-E

Boost Valve Kit 77898E-16K

Late style, .472" dia., OE ratio, O-ring style

    Helps cure:
  • 3-4 Clutch failure
  • 2-4 Band failure
  • Low line rise
  • Poor shift quality
4L60-E, 4L65-E Boost Valve Kit 77898E-K

4L60-E • 4L65-E

Boost Valve Kit 77898E-K

Early style, .490" dia., increased ratio, O-ring style

    Helps cure:
  • 3-4 Clutch failure
  • 2-4 Band failure
  • Low line rise
  • Poor shift quality
200-4R, 4L60, 4L60-E TCC Apply Valve Kit 77805-K

200-4R • 4L60 • 4L60-E

TCC Apply Valve Kit 77805-K

Fits non-PWM units only.

    Helps cure:
  • No lockup
  • Falls out of lockup when hot
  • Fluid blown out fill tube
  • Lockup immediately after 2nd gear
4L60-E, 4L65-E Boost Valve Kit 77898E-6K

4L60-E • 4L65-E

Boost Valve Kit 77898E-6K

Early style, .470" dia., OE ratio, factory style

    Helps cure:
  • 3-4 Clutch failure
  • 2-4 Band failure
  • Low line rise
  • Poor shift quality
200-4R, 4L60 TV Boost Valve Kit 77917-02K

200-4R • 4L60

TV Boost Valve Kit 77917-02K

.423" Bore Dia., Factory Style

    Helps cure:
  • Soft slide shifts
  • 3-4 Clutch burned
  • Reduced band life
200-4R, 4L60 Reverse Boost Valve Kit K77898

200-4R • 4L60

Reverse Boost Valve Kit K77898

Large Ratio, O-Ring Style

    Helps cure:
  • Low Reverse boost
  • Delayed Reverse
  • Low line pressure
  • Poor upshift in manual low
200-4R, 4L60 Reverse Boost Valve Kit K77898A

200-4R • 4L60

Reverse Boost Valve Kit K77898A

Large Ratio, Factory Style, No O-Rings

    Helps cure:
  • Low Reverse boost
  • Delayed Reverse
  • Low line pressure
  • Poor upshift in manual low
200-4R, 4L60 TV Boost Valve Kit 77917-500

200-4R • 4L60

TV Boost Valve Kit 77917-500

.500" Bore Dia., O-Ring Style

    Helps cure:
  • Soft slide shifts
  • 3-4 Clutch burned
  • Reduced band life
200-4R, 4L60 TV Boost Valve Kit 77917-04K

200-4R • 4L60

TV Boost Valve Kit 77917-04K

.500" Bore Dia., Factory-Style Sleeve

    Helps cure:
  • Soft slide shifts
  • 3-4 Clutch burned
  • Reduced band life
200-4R, 4L60 TV Boost Valve Kit 77917-03K

200-4R • 4L60

TV Boost Valve Kit 77917-03K

.471" Bore Dia., Factory Style Sleeve

    Helps cure:
  • Soft slide shifts
  • 3-4 Clutch burned
  • Reduced band life
4L60-E, 4L65-E Boost Valve Kit 77898E-3K

4L60-E • 4L65-E

Boost Valve Kit 77898E-3K

Early style, .490" dia., increased ratio, factory style

    Helps cure:
  • 3-4 Clutch failure
  • 2-4 Band failure
  • Low line rise
  • Poor shift quality
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