Yeah I know the shifter alignment has been posted numerous times, I have done the Alignment its pretty simple But, I have just replaced the shifter body (stock C6) in my 99, as you all know the 2 shifter body bolt holes are slotted, nowhere can I find info as to where the body sits whether its in the forward, center or rear position, so does anyone know, its not in the service manual. Ive had shifter issues for years and have used a few different shifters and have now gone back to original, they have all jumped out of reverse when backing up an incline, the original not so bad when the body is locked down in the rear position. I would really appreciate some ideas.

 

Transmission rebuild. The fork or fork pads for reverse are damaged.

Shifter alignment is not rocket science as you point out. There can sometimes be a sweet spot achieved, but if you're using the OEM pin to center the stick at install or adjustment then you are right in the ballpark already.

The T56 is a highly durable transmission. It will still run reliably when damaged or parts are broken internally. How many miles are on this one?

The slow way to save some cash might be if you are ok wrenching on your car yourself to buy one from a known quality donor car where someone is upgrading. Then sell your current one. It still works and has value even if it is a bit rough. One person's junk is someone else's gem.

 

Thanks Tusc

The fork and pads are what I'm thinking also and yes I may have to have it removed and repaired, I can't buy a used trans as Im in Australia and cant get one shipped from the USA Ive tried, in the past I would of pulled the box myself but I cant these days due to heart health and no workshop wants the car sitting on their hoist for several weeks while the box is off being repaired, its a catch 22.
But that doesn't answer as to how the shifter body should sit with the slotted hold down bolts. there isn't many C5s in Australia or I would ask someone to lift their shift boot and take a pic of the body located.

 

Slotted hold down bolts. Can you better describe which one(s) you mean?

The shifter itself has 4x bolts which secure it to the tub, but they are fixed and there is no slop.

There is the 1x bolt connecting to the linkage at the rear.

There are 2x bolts securing the tub arms to the torque tube.

And one factory shifters there is a pin up front which slides in when the shifter is perfectly centered - it can then be installed on the 3 bolts above and be reasonably centered as-is.

My simple approach is:
1 - center the shifter if possible
2 - tighten linkage bolt
3 - tighten 2x tube bolts pretty tight and row the shifter through all gears with attention to the outer edges like 1/2, 5/6, R and be sure the throw range is full.
4 - If the throw range is NOT full or easy, you can now gently force the tub fore/aft or side to side to get it better aligned. Once you have it where they all work, do the final full death grip tightening on those bolts.

Below is my best way to show a relational diagram. The shifter and tub are essentially the Green overlay and the T56 and linkage are the White. The goal is to get them to be as closely aligned as possible so each gear travels correctly and easily. There is rarely a perfect feel or overlay and that is not required. The transmission and linkage are static once the linkage bolt is tightened down. When you row the shifter you are making sure that as the geometry of where you are about to lock it in place allows for fair travel into all gears. So adjusting the shifter tub itself fore/aft, side/side affects that overlay. Sometimes if you have difficulty at this stage getting side to side alignment you may need to loosen the linkage bolt, move the shift handle a hair to one side and retighten. If you have trouble getting all the way into first gear then you might have the tub too far BACK and need to nudge it forward. Again, this isn't some high science, it is just a quick fit/align. I lock them down and drive them for a week. Then if I find I have an issue somewhere I adjust it. Sadly, not all shifters are made the same and this is why I have gone through so many. Though factory units should, by rights, be pretty easy to just slap in there and drive away.


In the three images above I am trying to show the following:

Left - the tub is too far to the rear, so the shifter movement range (green) slaps the stops in the 1/3/5/R gears but is not traveling as fully into 2/4/6. The correction is to shift the tub forward slightly. We also see the gears on the left are easily shifted but Reverse is hard to find and get into. The tub can be shifted to the right slightly, but perhaps the better fix is to loosen the linkage bolt and rotate the shifter itself slightly right before retightening.

Center - The tub is correct fore/aft fitment. But now the shifter gets into Reverse but has a heck of a time finding or being forced into 1/2. 3/4 is probably still fine. As are 5/6. Here again we can either shift the tub right a hair or loosen the linkage and bump the shifter left a hair before locking it down.

Right - Your generally correct and functional alignment which can vary from PERFECT to still taking some force but that is also a matter of comparing one T56 to another and their different conditions.

It is basically like a gun site. You adjust it in reverse clicks to center it. My description is far more involved than it needs to be. I literally tighten, slap around, adjust, throw it again, fix the last detail and go driving. You can also lock it in and go for a rip before reinstalling the dash pieces to save headache.

Good luck!

 

Hi Tusc.
The shifter Body that screws down onto the torque tube is where the 2 slotted bolt holes are, torxs head screws hold it firmly in place, But you have answered that question pretty darn well and with the diagrams that's the info I have never been able to find, when the car comes back I will play with the adjustment as per your info, thanks heaps well done, maybe that should be in the Sticky thread its really helpful info.

 

I appreciate your support. I hope that helps. Like I said, it's really simple... only three bolts to play with really. The only real random factor for anyone is the T56 you have. Some just never shift as smoothly as others, while some of those others you'd swear it was a 6060.

 

This is what I tell my customers. Like the examples above, I like to help people figure out how it works so they have an idea of what is going on if they have issues. Once you get a handle on how it works you'll be good to go.

Stock Box Alignment:
You do have to line up the box, but it takes little effort. There are some people who have trouble with it and there are a couple things you have to do to prevent that from happening. First you have to remove the little black, plastic foot from the fin on the bottom of the box. If your box doesn't have one attached when you pull it out of the car then you have to look down in the car. The foot seats into a little notch down on the side of the torque tube, sometimes they stick in the notch when you pull the box out. When you get an upgraded box you have to silicone the foot to the box and let it cure prior to installing, after it's cured, make sure you get that foot slid into the notch on the tube while you're installing it. Get the foot seated into the notch and you'll be able to slide the box fwd/rwd a small amount. Before you tighten the box down you want to get the shaft from the box into the (gold colored) collar of the linkage. Remove the bolt from the linkage first and clean the threads on the bolt and the threaded hole on the collar of the linkage. Slide the shaft into the collar, seat the box confirming that the foot is in the notch on the tube and slide the box fwd/rwd then back to the center and tighten the box down. Do not install the linkage bolt yet.

Shifter Alignment:
With the box centered and the shifter mounted to the box you can move the stick and see how the shaft from the box moves in and out. There is a small notch towards the rwd end of the shaft; this slot needs to line up with the bolt hole on the linkage collar. The bolt must travel through the collar and through that notch. This will position the stick correctly centered fwd/rwd. Center the stick right to left and insert the bolt into the collar, making sure the bolt travels through the notch in the shaft. Confirm the stick remains centered in all directions as you tighten the linkage bolt. This bolt is to be torqued to 22ft/lbs. You can break the collar if you over tighten this bolt and you will not be able to or lose the ability to get into first or reverse if this bolt does not remain tight. This is why we use RED (not blue) Loctite on the threads of this bolt and why it is important to clean the threads first.
Once you get this bolt tightened, test the car. Drive the car forward or backwards ten feet or so, then try shifting into every gear. Sometimes you won't be able to get into some gears without moving the car ten feet or so. It may be a little harder than you would like to get into first or reverse, that is normal. If you can get into every gear the alignment is correct, even if it requires a bit more force to get into first or reverse. This is because the box is not broken in yet, it will ease up after 100 miles or so as it breaks in.
After you have confirmed that the shifter is aligned correctly, center the stick one more time, remove the bolt from the linkage and apply a little RED Loctite to the threads, now it's finished.


Troubleshooting:
Usually you'll get all the gears on the first try, if not you have to adjust the box or the shifter depending on what the problem is. If you can get into the upper gears (1,3,5) but not the lower gears (2,4,6) it is a box issue (no adjustment needed for the shifter). If you can not get into 1,3,5 the box needs to be moved away from 1,3,5 (slide the box towards the back of the car).
If you can not get into first or reverse it is the shifter that needs adjustment ( no adjustment needed for the box). Loosen the bolt on the linkage and push the shifter a very small amount (about 1/16 in.) away from the gear you're having trouble with. (Towards the driver's side, for example, if you're having trouble getting into reverse).
Tighten the linkage bolt again, drive the car ten feet and try getting all the gears. If you go too far you will be able to get into reverse but you will now have the same problem getting into first instead, this means your adjustment was too big.

 

Which Sydney are you in? I'm planning on pulling the stock T-56 out of my '04 Z06 to put a built T-56 in it. I'm sure we could figure something out if you are on the East Coast of the U.S.

If you're in Sydney, Australia, it would probably be cost prohibitive to ship. LOL

 

I'm not the OP, but thank you for this info! I noticed that I have to push WAY over to the right and with some force to get into reverse after I installed an aftermarket shifter. I'll have to get back in there and adjust it how you described!

Thank you! It looks like I made the right choice ordering from you guys yesterday. LOL. I will definitely have to grab some more of your products!

 

You dont use centering pin??

 

Not that it is needed.

 

Sydney Australia is where I am, I can't even have one shipped here, Ive tried numerous times.

 

Mybe not, but being able to use it IS helpful.....