So second gear is a much larger issue and is almost certain a replace situation, where as over drive is generally a known issue and if repaired most of the time can be fixed w/o replacement. I'll let chat explain why, but generally you fix the line pressure you fix the issues, but not with second gear which is "standard drive".. Now it is possible too the clutch is toast, but not likely if repaired soonish.
In Chrysler/Ram RFE transmissions (68RFE and 545RFE), "hard shifts out of overdrive" usually indicate an issue with the Overdrive/4C clutch packs or the valve body. Standard (lower) gears use different clutch combinations and don't rely on the overdrive circuits, which are under higher stress. [
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For an in-depth visual breakdown of how RFE clutch packs function, and why overdrive circuits are so prone to failure:
https://www.youtube.com/watch?v=6gu17UAzIrg&t=2
How Standard Gear Shifts Work
Lower gears (1st through 3rd) rely on the Underdrive and Reverse or 2nd/4th clutch combinations. These gear sets handle high torque from a stop but are generally considered more mechanically robust. Shifts between standard gears usually feel smooth unless there is internal wear in the valve body or solenoid pack. [
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Why Overdrive Shifts are Different
When the transmission shifts into overdrive (4th, 5th, and 6th gears), the Overdrive and Underdrive (or Overdrive and 4th) clutch packs are engaged. [
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- High Stress Points: The Overdrive clutch is notoriously the weakest link in these transmissions. It handles high rotational speeds and the stress of locking up the torque converter. [1]
- Hard Shifting Symptoms: When a 68RFE experiences hard shifts out of overdrive, it usually means the transmission's computer is compensating for a slipping clutch or irregular fluid pressure. [1, 2, 3]
- Damaged Clutches: Hard shifts in higher gears are frequently caused by burned or delaminated overdrive clutches, which leave excess debris and cause erratic pressure
