Printpartsummary
Symptoms:
  • 2-3 Flare
  • Delayed Forward
  • Erratic SLT pressure
  • Harsh shifts
  • Low line pressure
Cause:

Line pressure control accumulator pistons are leaky, jammed or bound.

Correction:

This LPC accumulator piston is made of aluminum to match the expansion rate of the aluminum valve body (OE was steel). The piston restores SLT pressure and dampening. SLT is the boost pressure in this unit.

55-50SN, 55-51SN

LPC Accumulator Piston Kit

Part No.

59947-LPC

LPC Accumulator Piston Kit
  • 59947-lpc_combo

  • LPC Accumulator Piston Kit

Small_59947-lpc_combo Small_59947-lpc

55-50SN, 55-51SN

LPC Accumulator Piston Kit

Part No. 59947-LPC

  • Piston
  • Springs (2)
  • O-Rings (2)

Also fits AW55-51SN, AF 23/33and RE5F22A units.

Complaint:

  • 2-3 Flare
  • Delayed Forward
  • Erratic SLT pressure
  • Harsh shifts
  • Low line pressure

Cause:

Line pressure control accumulator pistons are leaky, jammed or bound.


Correction:

This LPC accumulator piston is made of aluminum to match the expansion rate of the aluminum valve body (OE was steel). The piston restores SLT pressure and dampening. SLT is the boost pressure in this unit.

  • O-rings eliminate fluid leakage between LPC piston and bore.
  • O-rings eliminate metal-to-metal contact between piston and bore that causes wear.

You need this if...

Vacuum test at the cover exhaust hole or accumulator entry port is below 18" of vacuum.

  • Test Locations

Click here to view PDF if instructions do not appear below.

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Valve Body Layouts

Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.

Valve Body Layout Aisin AW 55-50SN

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