1. 07.5-Current- Keeps the Low Reverse clutch from applying in the Drive position and allows venting to manual valve in Neutral and Park selection
- Failure if left out- If you forget this checkball #1 it will constantly feed Low Reverse in Drive which would be a bind when shifting to 2nd gear.
- P0841- L/R rationality code will be present.
2. 07.5-Current- This keeps the pump fluid off the manual valve from entering the Underdrive clutch circuit but allows the Underdrive clutch to vent to the manual valve when shifting into Park-Reverse-Neutral
- Failure if left out- No checkball in this location,harsh N-D engagement on all years also a bind shifting from 4th gear to 5th when the transmission needed to shut the Underdrive clutch off. With a P0876- UD
- Rationality code will be present.
3. 07.5-18- The duty of this checkball is to slow Rev clutch apply down but allow fast venting when you move the gear selector into
Park-Neutral
- Failure if left out- No failure other than harsh engagement on Rev apply.
19-current- This checkball is moved to the auxiliary body for these years, the duty of this checkball is to block the solenoid from venting and forces apply through R1 and R2 orifices.
- Failure if left out- It will send Rev fluid from manual valve to solenoid vent, which causes the clutch to slip/fail
4. 07.5-current- Blocks OD clutch from pump psi off the manual valve. This also allows venting of the OD clutch in Neutral in a failsafe/limp mode.
- Failure if left out- Would apply OD clutch in Drive position which would cause a bind when in 1st gear as well as UD leaks into OD which strokes the SSV to the lock up position which stalls the engine.
5. 07.5-current- This is how 2c and 4c are able to feed the SSV with 1 port. When 2c is applied it blocks oil from entering the 4c circuit and vice versa.
- Failure if left out- In 2nd gear it would bind up 2c and 4c clutch applying at the same time. You will feel a slight drag on the test drive with a P0988-Forth clutch psi rationality.
6. 07.5-11 (7ball)- The duty of this checkball keeps the Multi Select solenoid from venting the circuit out of the OD solenoid.
- Failure if left out- If you leave this out it will slip the OD clutch from the volume exiting through a solenoid venting. When it faults into Limp it will be neutral.
- Installed on 11-current- install on a valve body that doesn't require this checkball and it would block the OD end plug at the SSV from getting fluid to it.
- Which would keep it from holding it in the Lock-up position
7. 07.5-11 (7ball)- this checkball blocks 2c fluid from exiting through the Multi Select solenoid. It also allows 2c to be fed through the multi select in M2 gear position.
- Failure if left out- Would slip 2nd gear when engaged from venting the circuit out of Multi Select solenoid.
8. 19-current- This was installed for the shift feel coming out of Drive position. When shifted into neutral the checkball seats and makes the UD
clutch vent through an orifice.
- Failure if left out- No failure it would just be a more positive release from Drive to Neutral.
9. 19- current- This is for slow release of the input reverse clutch. When shifted to Park or Neutral it blocks venting out the manual valve for a
controlled release directed to the Rev solenoid.
- Failure if left out- no apparent failure point, this would have an unregulated release rate.
This tech tip was brought to you by:
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To help builders and DIY builders diagnose and understand the functionality of each checkball.
