Chrysler RFE Valve Bodies: Understanding Checkball Locations & Function

With the addition of the Chrysler ’19-later 68RFE valve body, confusion about checkballs has become an even broader subject. In this article we will explore RFE series checkball locations and function in greater detail.

It’s first worth noting that ’06–’10 45RFE, 545RFE, 65RFE, 66RFE and 68RFE valve bodies included seven checkballs in their design. Two checkballs were removed in the ’11–’18 RFE valve bodies (Figure 1).

Figure 1 – Checkball Locations: '06–'10 RFE vs. '11–'18 RFE Valve Bodies
*Checkballs #6 and #7 are not found in '11–'18 RFE valve bodies.

Checkball #1: Keeps low/reverse clutch from applying after the low/reverse solenoid is turned off in 1^st Gear. If the checkball is not present, low/reverse clutch is applied by the manual valve position, and it will cause a bind in 2^nd Gear. Code P0841 pressure switch rationality may be present.

Checkball #2: This checkball, if not in position, will cause harsh Neutral to Drive engagements, as it bypasses the UD solenoid feed to UD clutch with full line pressure. It will also cause an immediate bind in 4^th and 5^th Gear because UD clutch can’t be disengaged. Code P0876 pressure switch rationality may be present.

Checkball #3: This checkball, if not in position, will cause firm Reverse engagements, as its purpose is to direct reverse oil through an orifice. This checkball softens engagements into Reverse during garage shifts. Some performance valve bodies leave it out.

Checkball #4: This checkball, if not in position, will cause TCC to kill engine in Forward. Here is how: it bypasses the OD solenoid (early valve body) and is after the MS solenoid (late valve body), which then allows it to fill OD clutch circuit in Forward. That is simply direct gear — no problem. However, it also moves the position of switch valve inboard. Additionally, the low/reverse solenoid is on in Drive first, which, due to switch valve position, it now brings on converter TCC instead of low/reverse clutch. Code P0871 pressure switch rationality may be present.

Checkball #5: The purpose of this checkball is to separate 2C and 4C oil. It will cause a bind in 2^nd Gear because, without the checkball in position, it feeds both 2C and 4C. Code P0988 for 4C pressure switch rationality may be present.

Checkball #6: The purpose of this checkball is to separate OD clutch oil between MS solenoid and OD solenoid. However, due to OD solenoid being a normally vented solenoid, if this ball is not present, it vents OD apply oil at the OD solenoid circuit when MS solenoid is controlling OD apply. That will cause a neutral on OD shift into 4^th Gear. 4^th Gear limp in will be neutral, but M2 limp in will be normal.

Checkball #7: This checkball, if not in position, will cause loss of 2C apply oil. This occurs because, without the checkball in place, it dumps 2C oil at rear of manual valve. This causes a 2^nd Gear neutral condition. Due to 2C solenoid being normally vented, M2 limp in is also neutral condition. Code P0846 pressure switch rationality may be present.

Additional reconfiguration of checkball locations is worth pointing out when assessing ’19-later 68RFE valve bodies (Figure 2).

Figure 2 – Checkball Locations: '19-later 68RFE Valve Body

Checkball #3: In 2019, this checkball moved from main valve body casting to join circuitry with the #9 checkball. Its purpose is to limit the apply and release of reverse input clutch. On apply, it unseats and allows the R2 orifice to additionally feed reverse clutch. On release, it seats and routes reverse release oil through R1 orifice. Leaving this checkball out would increase release rate of reverse clutch.

Checkball #8: This checkball is unseated during apply (nonrestrictive) and seated during release to allow the UD solenoid to control the release of UD clutch.

Checkball #9: The purpose of this checkball is to seat on apply of reverse clutch and route oil to the reverse solenoid through the R1 orifice, therefore slowing down reverse clutch apply slightly. When the reverse clutch releases, this ball is unseated, meaning it's not restricting release at all. Note: the only time the reverse solenoid is used is for garage shifts to soften apply and release.

References and nomenclature used in this article are from the factory service manual hydraulic circuit diagrams.

Jim Mobley is a Sonnax technical communication specialist. He is a member of the Sonnax TASC Force (Technical Automotive Specialties Committee), a group of recognized industry technical specialists, transmission rebuilders and Sonnax Transmission Company technicians.