Can't shift from 5th to 4th?

[atl02wrx]

'92 TSi AWD 5-speed... It up shifts from 4th to 5th fine. What would prevent me from down shifting from 5th to 4th? It's like a wall, it just won't go in. This happens whether or not the car is moving. I did swap in another output shaft to this one so I had the 5th gear cover off. I doubt I put it back together wrong as it's fairly straightforward. I also tried removing the reverse light switch to see if it was a problem, but no change.

I couldn't find anything on here regarding 5-4 shift issues.

More background that may be pertinent to the question at hand...

I recently swapped trans because of a 2nd gear grind. I probably should have done more reading before jumping on a replacement trans, cause that one grinds too. Meh. The old one seems better off as it would only grind up shifting above 5500 rpm or down shifting above 15 mph. It didn't have any issues ike the 5-4 shift.

Since getting the trans in I've learned a lot searching the forums. I've ordered some different trans fluid, got a pedal rebuild on the way from JNZ, replacing some of the bushings under the hood, etc. The current clutch pedal does have slop in it. That's all basically to freshen the car up and see if 2nd can be fixed.

New RRE flywheel and pivot ball were put in with existing ACT clutch and pressure plate while doing the swap. Previous owner had that clutch put in less than a year / few thousand miles ago along with fork, throw out bearing, stainless lines, slave and master cylinders.

 

[dsmdeliveryboy]

Could be the synchro, check your clutch master and slave cylinders along with the clutch fork.

 

[XyoungmurdaX]

change the slave and the master cylinder. mine was very very stiff kinda like yours it helped a lot after the master and the slave it improved the most when i got my new clutch

 

[atl02wrx]

I'll post updates to this until the day comes I can mark resolved...

This weekend I'll be rebuilding the pedal with new hardware and installing Shep's pedal bushings and shift cable bushings.

I managed to bleed the slave again. I peeped behind the slave dust boot to find it bone dry so that's good. I did observe there doesn't appear to be much range of movement. Leads me to think the clutch pedal is culprit.

I also swapped the fluid from Redline MT 90 to BG SynchroShift II.

No improvements in shifting yet.

 

[atl02wrx]

It took me a little longer to get around to rebuilding the clutch pedal. First of all, getting it out isn't as bad as all the threads make it out to be. Sure I wouldn't want to do it again, but I was expecting a royal PITA.

Clutch feel has improved significantly and no longer engages "off the floor" like before. I adjusted master cylinder rod clevis pin play to factory spec. Slave cylinder throw seems to be more than before (wish I had measured it). Shifter cables are adjusted to factory spec as well.

However transmission shifting hasn't improved much. 5-4 issue still there. 2nd grinds anywhere above 2k rpm. I think I have a bad tranny

Grasping at straws here. Any hope of adjusting out the master cylinder rod improving shifting? What about installing an extended slave rod?