have a new transmission from passon installed over a year ago (still the 4 speed just beefed up) problem is when I go into 4th gear, the minute I get off the gas the pistol grip moves back into neutral. I know how to set up the hurst shifter properly with the alignment pin, I've adjusted the 4 link arms to both extremes but with no luck. My shifter is very easy to move, I rebuilt it a few years ago, maybe its too easy? What's a new shifter like? Are they pretty stiff? I do have a hydraulic clutch installed and I've tripled check to make sure I have the proper clearance from the clutch fingers to the throwout bearing when disengaged,
My car is a 71 runner for reference...

Check for contact between the rod and the frame. My Challenger would do that when the transmission mount started to go.
Another thing to look for is worm lever holes or fork shafts that prevent proper engagement.

Hope it helps.

I have new clips/washers and the arms are new so there isn't any slop, I'll check to see if its touching the frame anywhere - The transmission mounts and motor mounts are new.

I couldn't feel the slop until I loosened the nuts on the side of the lever. The lever hole had wallowed out and the shaft worn too. Mostly because i didn't have positive stops and over time banging through the gears took it's toll.
When the nut was tight it felt fine but when I shifted it would move.

I have had a bad gear tooth do that.

oh please I hope its not this, the transmission is not that old!



I'll have to pull my shifter apart and have a look

I had one that did that. The trans and link rods were all original so there was probably some wear as described above but a stiff rubber shifter boot was the culprit in my case. I replaced it with a fresh repro boot and never had the problem again.

Bell housing misalignment will also cause it to pop out of 4th gear. Is the bell original to the engine?

its a aftermarket bellhousing from american powertrain

Did you dial indicate it in when you installed it?

Kevin

If it's a bellhousing alignment issue; why would it only effect 4th gear?
I always thought that worn/misaligned syncro teeth/gear issues cause trans to "pull" out of gear.
If a stiff shifter boot will pull a trans out of gear, I'd suspect synroc aren't working 100%.

If the bell is out of alignment, it tweaks the input shaft off center. 4th gear locks the input shaft to the main shaft. If the input isn't aligned properly with the main shaft, it can spit it out of gear.

If the bell is dialed in, the next question is did the input shaft get replaced when the trans was built?

Kevin

I'd suspect synroc aren't working 100%. i too have seen this many times... the bell housing may be it. but, whats known about the trans condition?

Seems plausible. In/Out ratio is 1:1 in 4th only.