Notchy shifting
Melting Slicks
Joined: Dec 2018
Posts: 2,654
Likes: 1,386
From: Orange County, CA
The only thing that's different between engine off and engine on related to shifting is a spinning transmission input shaft. Based on that perspective, I have some ideas:
My suggestion would be to drop the clutch inspection cover to get a better look at the clutch's operation. Gotta drop the midpipes to access it.
- Misaligned shifter
- Try a shifter alignment, it's relatively quick and free.
- I'm not optimistic about this having a positive result since I'd imagine a misaligned shifter probably would cause notchy shifting with engine off.
- Clutch isn't disengaging completely, which means the input shaft isn't slowing down appropriately
- The transmission's synchros have the job of braking the input shaft, but it's hard for them to do this if the input shaft is being actively driven while the clutch pedal is depressed
- Could be related to clutch fluid, but could also be related to clutch master and/or slave cylinders
- Could also be related to clutch/pressure plate itself
- Transmission isn't adequately lubricated, synchros might need more or better fluid
- Drain & refill trans fluid. Many people have reported improved shifting characteristics from a fluid change.
- Transmission has worn synchros
- Not as likely if the behavior you're experiencing occurs in most/all gears
My suggestion would be to drop the clutch inspection cover to get a better look at the clutch's operation. Gotta drop the midpipes to access it.
Tech Contributor
Joined: Jan 2007
Posts: 19,456
Likes: 1,164
From: Dyer, IN
Melting Slicks
Joined: Dec 2018
Posts: 2,654
Likes: 1,386
From: Orange County, CA
For better or worse, I made the assumption that shifting is notchy as soon as the engine is fired up and trans fluid is still cold.
