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45RFE 545RFE 68RFE Transmission 4C Retaining Ring & Shim Kit Sonnax 72978-01K

by Sonnax
SKU S72863HDK
Original price $17.74 - Original price $17.74
Original price
$17.74
$17.74 - $17.74
Current price $17.74
Availability:
in stock, ready to be shipped

Delivery time

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

Non-Domestic Product: No

Custom Bundle: No

Fitment Type: Performance/Custom

Items Included: Retaining ring, G-lock ring, Shim

Manufacturer Part Number: 72978-01K

Drive Type: 4WD,AWD,RWD

Material: Steel

Modified Item: No

Placement on Vehicle: Front

Brand: Sonnax

Type: 4C Retaining Ring & Shim Kit

Core Charge: No

Interchange Part Number: Dodge Jeep Ram 65RFE 66RFE 68RFE

Manufacturer Warranty: Unspecified Length

Surface Finish: Brand new

Country/Region of Manufacture: United States

45RFE / 545RFE/ 65/66/68RFE 

4C Retaining Ring & Shim Kit
Part No. 72978-01K

The 4C return spring retaining ring in Chrysler 45RFE, 545RFE, 65RFE, 66RFE and 68RFE transmissions is known to come unseated and pop off, resulting in transmission failure. To repair and prevent this problem, plus more easily tune 4C performance, Sonnax offers 4C retaining ring and shim kit 72978-01K with three essential parts for a reliable build.

The custom G-Loc ring in the Sonnax kit mechanically holds the OE retaining ring in place to prevent it from popping out.

The kit’s .078" thick clutch backing plate retaining ring makes it easier to achieve the 4C clearance specification of .030 to .055". Setting this clearance is difficult when OE selective backing plate retaining rings are not readily available. As a result, some builders use thinner steel plates, but this undermines the clutch pack’s ability to dissipate heat. The ring in the Sonnax kit is .010 " thinner than the ring most units have from the factory, allowing for more choices when setting clutch clearance.

The spring pack shim in the kit gives the option slightly tune the 4C clutch to release more quickly. Combining the shim with the thinner backing plate retaining ring and setting clearance closer to the high end of spec will preload the return spring for increased force. The result is improved 4C to OD shift timing when more aggressive, quicker-applying OD clutch packs are used.

  • Prevents 4C return spring retaining ring from popping off
  • More options when setting clutch clearance
  • Improves 4C to OD shift timing
Contents
  • Retaining Ring .078" Thick
  • G-Loc Ring
  • Shim

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