Shifting focus
 

The long and short of it, details below.

Tl:dr exactly the same hard shifting despite changing transmission, what should I change/check?


OK here is a odd one.


I am having “issues” with shifting, where it feels like it is taking much more effort to select a gear than it should, and indeed ever did before with no changes to the setup or assembly.

Particularly first and reverse when parked.


1st transmission:

I though it must just be the transmission giving out or hopefully the lubricants giving out, so I replaced with high end fluids, and instead of helping the condition, it actually aggravated the problem!

The issue seemed to have crept up over ~ a year and seemed more noticeable when it was cold, but eventually became a temperature independent issue, all the while getting progressively more and more noticeable.

While I would never say it was “super easy” to shift with this transmission, it was never even a conscious thought and moved into the desired gear without fanfare. Unquestionably easier in comparison to its present state of operation.

My thoughts were: transmission on its way out, old diff bushings causing issues, old fluids, age.


2nd transmission:

So I got a new low mileage transmission thinking I will just bypass any issues I was having.
New neo oil for both the trans and diff, new diff/suspension bushings, and many other little cleaned and serviced parts.

Put everything back together.......
Exactly the same patterning and feel of hard/difficult shifting.
I feel absolutely no difference in the way it did feel, and the way it feels now.




What do I do?
Where does the issue lie if not in the transmission itself?

Can something else cause this kind of condition?
The drivetrain seems to move and rotate very smoothly and quite easily with no binding.

The best way to describe the difficulty in shifting is that it feels like the whole assembly from the gear shifter to the diff needs to be moved for the gear selection to take place.

It is a very heavy feel, and with enough pressure it forces itself into gear with a fairly hard clunk both with the new trans and old.

As with the old trans the new seems to work fine as long as the vehicle is moving, I would not say it is easy, but acceptable, if memory serves, it seemed easier before while rolling.

Both shift quite smoothly when out of the vehicle.

Pertinent parts:
B&M Short shifter has been on since well before any issues. (still in new condition, no slop new shift bushing)
Exedy twin carbon
Old stock/new diff bushings give no change in operation
Neo trans and diff oil


What descriptions could I give to indicate where this issue is coming from?

This could possibly be caused by something not allowing the engine to fully disengage from the transmission. Clutch not releasing completely, or maybe the pilot bearing is binding up. Did you inspect the condition of the pilot bearing last time you had it apart?
Also, what does your clutch pedal "stroke" feel like? When you start off from a stop, does the car start moving when the clutch pedal is barely off the floor? Or midrange or near the top of the pedal stroke?

Sounds like clutch. A cracked release fork, damaged wedge collar / ring, or bum hydraulics.

If the transmission shifts much better with the engine off / car parked, focus on the clutch.

Dave

Stock shifting is like butter. I'd guess clutch, fork and/wedge collar as mentioned above.

don't subframe bushing affect shifting?

Well its seems painfully obvious to me now.
All the mechanical components mentioned are operating fine and look great.

The one weak point seems to be the hydraulics.
Of which as long as they are operating and no leaks can be found as well as being well bled didn't really occur to me as a possible problem...


I now believe this is where the issue lies.

The clutch throw is now maxed out, if I artificially increase the throw by moving the adjustment rod far beyond normal positioning, it seems to cure the issue slightly.
Though not enough to make any definitive assertion.

But for the life of me I cannot think how this could be possible.

What makes the throw of the master and slave system decrease?

Can there be air trapped somewhere in the master, or in a small cavity I have not considered?
Any good ways to be sure the entire system is bled correctly? Master,Slave, and any component inline or that could cause an issue?

And ways to find where/what the actual issue and/or culprit is?


What are possible problems with this system that could cause these symptoms?

Is there any ways to completely be sure of the issue?


I have heard of issues with masters that have air in them, that are almost impossible to cure.

Can anyone describe how hard it is to get a optimal system if air were to get into a undesirable place on this particular system?

Does anyone have some advice on this matter they could pass on?

Has anyone had a condition like this where it was not just air in the hydraulic system?

Or perhaps air that was difficult to remove?


Any tricks to getting hard to remove air out of the clutch system?
It has been bleed well.
Is there a place for air to hide in there?

What else could it be if not air?
There does not appear to be any mechanical wear in the linkages that could account for the lack of throw.

Can a master cylinder go bad? And if so how?
I bleed the system again just for good measure, and it seems to be getting worse not better?


How far does the throwout bearing typically move in inches from full release to full engaged?