Symptoms:

  • Delayed engagement
  • No Forward
  • NIC (Neutral Idle Control) concerns
  • Gear ratio & solenoid codes
  • No Reverse
  • B Clutch burned
  • Flare shifts
  • Harsh shifts

Cause:

B2 clutch NIC valve oscillation promotes bore wear, which causes drivability concerns by allowing vital pressure to escape the circuit.

Correction:

Stop leaks and renew shift performance by reconditioning the bore and installing Sonnax oversized B2 clutch NIC valve.

845RE, ZF8HP45, ZF8HP55, ZF8HP70

Oversized B2 Clutch NIC Valve
Part No. 35740-22

ZF valve name: KV-B2
Chrysler valve name: CV-B2


You need this if... View Instructions Find a Distributor

The B brake clutch in Chrysler 845RE, ZF8HP45, ZF8HP55 and ZF8HP70 transmissions is applied in Reverse, and 1st through 5th Gears, and maintains a controlled slip during neutral idle control (NIC) conditions. The B2 clutch NIC valve provides pressure to the release side of the B clutch piston - so clutch release is controlled by hydraulic pressure and not a return spring. As the B2 clutch NIC valve oscillates and strokes over time, bore deterioration results, allowing critical release pressure to be be compromised. This can cause harsh shifts, Forward and Reverse engagement concerns, flares, ratio codes, and neutral idle control concerns. Reconditioning the bore and installing Sonnax oversized B2 clutch NIC valve 35740-22 revives normal shift operation by eliminating the wear that causes circuit leakage.

  • Lengthened critical spool for added stability
  • Hardcoat anodized aluminum valve combats premature wear
  • Relocated annular groove maximizes valve centering, helping to avoid excess side-load wear

Some Audi M-Shift applications do not have a valve in this location. Do not install Sonnax valve into a bore that did not contain an OE valve.

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.

ZF8HP55 Valve Body Layout

ZF8HP55 Valve Body Layout

ZF8HP45, ZF8HP70 Valve Body Layout

ZF8HP45, ZF8HP70 Valve Body Layout
  • 845RE, ZF8HP45, ZF8HP55, ZF8HP70 Oversized B2 Clutch NIC Valve 35740-22

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

845RE, ZF8HP45, ZF8HP55, ZF8HP70 Oversized B2 Clutch NIC Valve Vacuum Test Locations