Skip to content
Sonnax 55209-01K 5L40E 5L50E A5S390R A5S360R Transmission Boost Valve Kit

Sonnax 55209-01K 5L40E 5L50E A5S390R A5S360R Transmission Boost Valve Kit

by Sonnax
SKU S144507RK
Sold out
$38.11 - $38.11
$38.11
$38.11 - $38.11
$38.11
Availability:
Out of stock

Delivery time

You will receive your package in 2–5 business days within the contiguous U.S.

Manufacturer Part Number: 55209-01K

Brand: Sonnax

Fitment Type: Direct Replacement

Manufacturer Warranty: Yes

5L40-E, 5L50-E

Boost Valve Kit
Part No. 55209-01K

Performance ratio with .531" & .492" dia. valve spools.

Vehicles with GM 5L40-E and 5L50-E transmissions are prone to poor line rise or high Reverse pressure problems causing poor shift quality and clutch failure due to leakage at the boost valve assembly. Sonnax offers two boost valve kits: the 55209-01K performance ratio (higher line rise and firmer shifts) and the OE ratio 55209-04K for factory performance.

  • Hardcoat anodized aluminum valves combat premature wear
  • Boost sleeves are made from alloy aluminum specifically designed to resist wear
  • Increased performance ratio 55209-01K or OE ratio 55209-04K kits are available
  • Valve
  • Sleeve
  • Spacer
  • Dia.: 0.531"
  • Dia.: 0.432"

Use this text to share information about your product.

Blog posts

See more