C5Z, came with a C6 shifter. When I purchased car, it would sometimes be hard to go into 1st. It would go part way, then stop. Would have to release clutch, then shift into 1st. Also often difficult to downshift into 2nd, goes part way, then stops. I changed clutch, slave, upgraded To Tick MC, and it seemed to be better, but will still do it a good bit of the time. I did Anti Venom mod and it made things smoother, but still same issue.

I played with shifter some today after driving. It will hang up abut 1 in 5 times going into first. Usual when it works, it feels like it passes a little pressure point half way through shift, then it goes into gear. When it doesn't work it hangs up on this pressure point, like it hits a wall. I noticed today, it will only hang on the initial engagement of the clutch. Meaning, if it shifts the first time, and I keep clutch in, it will shift smoothly over and over, and never hang.

Does this sound like a shifter alignment issue? Since I have changed clutch etc., and did the same before and after, I wouldn't think it would be clutch, but why does it not hang up each time, and why will it never catch if it goes in gear and I keep clutch in, and can shift over and over?

Thanks

 

Sounds like worn blocker rings in the trans. Did you change the trans fluid when the clutch was done?

 

No, but I am planning on doing that and the diff in the Spring.

 

Since the problem seems to be only on one side of the gate (1st & 2nd gears) it sounds similar to a problem that I have on my Z. With mine it does seem to be a shifter alignment problem caused by wear in the lower shift box. I also have a C6 shifter in my '04 Z. Over the years the amount of play from left to right in the shifter when in neutral has gotten wider. I can jiggle the shifter **** between 1/4 and 1/2 inch from side to side now. I need to pull the shifter pretty firmly to the left when shifting into 1st and 2nd. Occasionally I'll to the shifter alignment routine to keep things centered and it usually helps. Eventually I'm going to need to get a new lower box, or, see if I can install a bearing in the rear of the box where the shifter shaft passes through. If you haven't tried an alignment lately it can't hurt to try.
Good luck!

 

Is this common with only about 53k miles?

 

I,am hoping it is just an alignment issue. I have never aligned it, was planning on doing it when I do a stereo install, as I didnt want to take apart twice, but may, as I don't know when I will get to stereo.

 

I would 1st check to see if it's your clutch---They need to be "bled" from time to time to get any air bubbles out---Quite simple---Usually 1st gear needs the clutch to be in all the way--If any air gets in it won't

 

I mentioned I changed clutch etc., and it did the same before and after.

 

It still can be either the clutch "slave cylinder" or the clutch "master cylinder" that needs to be bled correctly

 

No, it's not the hydraulics. It's the transmission. I experience the exact same symptoms.

 

Any resolution? What make you think it is the trans? Do you have stock shifter?

 

Resolution was a transmission rebuild. The reason I know it's the transmission is because the transmission was taken apart in front of my eyes. I had several worn synchros, and shot gears.

Before I took apart the transmission I had both a Hurst and Stock shifter. The stock shifter made shift effort go down, due to sweep length being longer, but the same behavior was there. You can tell if it's the actual shifter which is your problem by removing the box from the car and rotating it several times.

Shifter alignment doesn't help with this problem. The alignment does make the linkage go into slot more easily, but the problem in this case are the transmission internals themselves.

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I should clarify: I completely replaced all clutch hydraulics (AKA DROPPED THE ENTIRE DRIVE TRAIN). Was clutch engagement smoother? Yes. Was the pedal action quicker? Yes. Did it change my issues with getting into gear? NO.

I'm just trying to save you some time (and money). It's a tough pill to swallow, rebuilding a transmission. Hopefully when mine gets back it will be as good as new. These T56's are really fragile.

 

How many miles was on the trans? Hard miles or normal street?

 

Here is a link to a short video that explains how the synchronizers and blocker rings work. The blocker rings I mentioned in post 2 are the brass parts that have been updated to a newer design in the t56. If they are worn, you will have the symptoms you describe

 

Thanks, interesting. I would think third and fourth would tend to wear out first, with missed shifts.
It never does it shifting from first to second, only downshifting from third to second. Does that make sense?

 

97,000 miles.

 

Mine had the issue when I got the car, with less than 50k.

 

I have that issue(sort of)as well.
Difficulty getting into first all the way is my only problem. Got the car with 64K, now at 67K and getting new clutch but the list is growing as I'm spending more time here!

 

This problem can be caused by all kinds of things.

Start with the simple - make sure there is no slop in the clamp at the rear of the shifter box on the rail leading to the tranny, and check the shifter box for wear/slop.

I pulled mine out recently because of noticeable side to side "slop" - it was the clamp. Though it was tight to undo, it clearly was not quite tight enough and it was allowing just a little movement. Replaced it, along with a new bolt, Loctited and torqued to spec. Other possible problem is failed rubber bushings to the torque tube, allowing the box to wriggle a bit.

Two areas that wear in my experience - the bushing at the rear of the box, and the ball and its bushing, which are trapped in the top part of the box - cover plate riveted on.

Saw both on my original (70k) shifter box, but they don't contribute more than a fraction of an inch of slop at the ****, but I did drill out the rivets and tightened things up some by judicious use of emory cloth where the rivet on plate meets the top plate of the shifter box proper. Then 3/16 bolts with locknuts and Loctite to put it back together. Not much you can do about the rear bushing unless you have, or have a friend with a lathe to turn a new bush - they are not service parts, apparently. If it's all to he!!, get a new box - vendors on here sell the C6 set up which fits right in, and they are not expensive.

Another simple thing is tranny fluid. I found a new fill with non syn DexIII (used Valvoline DEX/MERC) helped a lot with my balky 1st-2nd shift, and occasional balkiness getting into 1st when stationary.