Step-by-step T-56 rebuild with pics!

[NBMWSsix]

Gonna rebuild your own tranny? Step-by-step right here:

The tranny used was previously rebuilt by who knows? This rebuild was my first. It was very confusing at first. I used the T-56 service manual and the Shifting Six with Confidence article used High Performance Pontiac. It takes a few hours from start to finish if you know what you are doing. If not take it slow and place pieces in sequence the way you take them off on a separate table. I also recommend taking pictures with a digital camera to see how things go back together in case you don't remember. I could only work on it on weekends so I would have to look at the pics and the service manual. Printing out this thread wouldn't be bad idea either.
NOTE: If you dis-assemble the synchro assembly(slider&hub) as pictures indicate, be sure to re-assemble them the same way. These are marked with a laser marking to show the original orientation. This will insure the proper fit of the parts. Excessive loosness (rock) can cause gear jump out and general shift complaints.
Handling of the parts with the bearings installed requires some care, too. It is very easy to bump the mainshaft pocket bearing and not know of the damage untill you do a drive test. A little extra care can save some serious strings of foul language later.
Lastly , keep every thing clean. Even simple lint / threads from rags can be a detriment to a favorible result.

Tools needed:
When it comes to tools with the exception of the gear puller I fabricated I bought quality tools. IT will save you a lot of time if you have the right tools.
SOLD WORK TABLE With a good sized opening or separation since the tranny will be verticle for most of the process. The opening is for the input shaft of the transmission.
SNAP RING PLIERS for both styles - Slant tipped and hole tipped. The snap rings used on the transmission are heavy duty and WILL either bend or break your "El Cheapo" brand snap ring pliers. Craftsman or a good name brand will do well. Trust me on this that was $4.99 down the drain.
GEAR PULLER - Professional ones range from $80 to $200. I made my own for about $20. I got the largest 3-sided gear puller I could find for like $9. It was too short so I went to Home Depot and got a couple of metal strips that were the same width and thickness, cut them to about 12 inches in length. I then drilled holes spaced about 1 inch apart on one end to make it adjustable length. It worked perfect.
HOLLOW PIPE large enough to fit over the mainshaft.
HAMMER Used when you need a little extra effort. Not to be used out of frustration.
SMALL OR MEDIUM GEAR PULLER to remove teh speed sensor and the 3-4 synchronizer hub.
T-30 OR T-40 TORX BITS to remove teh two torx screws on the side of the case.
Here are the speciality tools:


Parts Replaced: - 1-2 Synchro keys, 3-4 shift fork, 3-4 synchro keys, 3-4 gear blocker rings, C-springs for both housings.

Synchro assembly from the T-56 manual:


C springs for the inner synchro housing. The gear blocker rings were also showing signs of wear so those were replaced as well. Worn blocker rings with paper like linings, these were replaced.


First thing that should have been done is to drain most of the fluid out of the tranny for two reasons. When you start lowering the tranny it will start to leak out the rear seal and all over you. The other reason is the tranny weighs about 100 lbs bone dry so you can do yourself a favor by getting rid of that extra weight.

This picture I am removing the rest out of the rear part of the case so that it just doesn't make a mess. I put it in the bucket to inspect what settles at the bottom, metal shavings, broken pieces, etc.


Next remove the two bolts off the front of the transmission that hold on the slave and remove the slave. You will notice that there are several bolts that may be hard to notice because of clutch disc dust. Remove all but two of these, on opposite ends from each other. Loosen these two leaving about 1/4" between them and the plate.
These bolts are circled in red. Should be 11, but I could have missed one.


Next place your bucket under the front plate. Using a large screwdriver or similar tool we want to pry open the plate from the case using the pry spots. You may need to used the hammer to get it started. Be careful not to gouge the surface where the plate and cover come together. These trannys don't used gaskets and you will end up with a pemanent leak. They cannot be machined either because things won't line up inside.
Pictured here:


After removing all the fluid re-tighten the bolts (hand tight) and turn the tranny upright. Using a punch or similar you will want to remove the shifting saddle pin. Then slide off the saddle.

[NBMWSsix]

Remember to tap the pin partially back in to the saddle afterwards or you will risk losing it.


Using hand ratchet and socket you will want to hand loosen the bolts holding the rear casing on. After loosening them you can use an air ratchet to finish removing them.


Using your screwdriver locate the pry spots and separate the rear casing from the main body. Keep in mind to not scratch the surfaces.


Then after you have separated them simply lift off the rear casing.







From here the case magnets will be visible. If there is debris larger than what is pictured, that could be one sign that something more serious is going on inside.


First thing to do is remove the rear seal that will be on the mainshaft. Below it will be your first slant tip snap ring. Remove this and use a gear puller to remove the speedometer sensor [also known as the VSS] pictured below.


Next remove the two snap rings and bearing to remove the reverse gear.


Next remove the snap ring holding the reverse synchro housing in place.

[NBMWSsix]

Before attempting to remove the reverse synchro assembly don't forget to take off the snap ring holding the reverse shift fork on the shift rail.



Now it's time to bring out the big boys! Grab the super duper gear puller and set it up to its longest setting (if you made one like I did) to reach the 5-6 gear. Using a hand ratchet and socket, start to slowly remove it and after a while it should slide off freely.


It's sort of difficult to see but in this picture there is another snap ring that must be removed before taking out the back section of the countershaft.


Now slide out the fork and the countershaft together.


Next using a T-30 or T-40 torx bit, remove the alignment screws on the side of the case.


Now you are ready to remove the main casing off of the front plate. When doing this keep and eye on the shifting pattern piece(circled in yellow), when it comes off the rail it will want to pop off due to the spring and ball bearing that is inside it. Be careful not to lose it.


Now inside the front of the main case we have the 1-2 and 3-4 gear and related components. You can lift the mainshaft and the shift rail together to separate the forks and rail from the mainshaft. You can then set the mainshaft back and remove teh little rubber seal holding the large race bearing. Remember to take it out first. That is the only thing hold the bearing in place.


Here is what we are looking at. On the left is the mainshaft shiftrail. Then the mainshaft in the middle with 3-4 assembly on the bottom (blue) and the largest assembly is the 1-2 near the middle of the mainshaft (yellow). To the right is the countershaft (red).

[NBMWSsix]

I inspected the parts according to the service manual and found all them to be fine except the pieces replaced.
I replaced the 3,4 shift fork with a steel one. I replaced the 3,4 synchro housing along with the keys and C-springs. There was also a plastic spacer behind the third gear that had partially melted into the 3,4 synchro housing. This was replaced by a steel spacer. If you have a 2000 or newer you already have this steel spacer.

Oh yeah DO NOT remove bearings unless you need to replace them. All the parts slide over them so don't waste your time. They are a PITA!

Front plate and the infamous 3,4 synchro still on the mainshaft. The snap ring on the plate on the left has to be removed prior to removing the 3-4 synchor hub. Using the smaller gear puller you can pull off the hub after you have removed the outer synchro sleeve, keys, C-springs.


Here is little description of what some of the parts look like (don't be scurred):


Final Product...it's....so...beautiful!


The famous T-56 service manual with custom cover made by me.


I also re-tightened the snap rings using a hammer and banging on them to close them a little so they would be tight on the shafts.
NOTE: "You discuss"resizing " snap rings . This is generally a bad practice. If they require resizing, it most likely due to over-expansion. It is a better practice to use new rings. This allows only one expansion ( for install) an reduses the risk of a cracked ring developing into a broken ring down the road.It is most critical , though , that one is sure all rings are fully seated in their respective groove.It is easy to mix the snaprings as well so to lay them out carefully is also a good move." -30THBIRD

After reassembly, you should seal the case with silicone. Do not put tranny fluid into the tranny until the silicone is dry.

Results:Prior to install I went thru the gears with the shifter and everyting was very smooth. I also did the McLeod master bleed and Thanks to Buschman's/NBMWSsix Tutorial the clutch is very solid.
The tranny was installed Monday. It takes 4 quarts of fluid. I started up the car and there was some noise from the tranny until everyting got covered in fluid then it quieted down. I took it for a test drive and every gear was smooth. Took it out on a very quiet road and let loose. 1st, 2nd breaks the tires loose easily. 3rd has a very pronounced bark. 4th,5th,6th very smooth. Took it up to about 120mph no problems. So the sleeper has awakened again...

P.S. If anyone is going to attempt this I can give u some pointers or answer questions to the best of my knowledge. Overall it was a great learning experience and not as difficult as I expected. I am glad I decided to do it.

Credits: Thanks to LS2.com (30thbird/JMWS62001), Installuniversity, High Performance Pontiac Magazine, Buschman's Tutorial, Rockland Standard Gear, and God because only he knows how I managed to figure this out by myself.

[FlagSStaff]

Hol E. Cow! I very rarely spend time readin long posts, but I read every last word of that and I must say... I *almost* have enough NuTz now to do my own!

NBMWSsix

[NBMWSsix]

Originally posted by FlagSStaff
Hol E. Cow! I very rarely spend time readin long posts, but I read every last word of that and I must say... I *almost* have enough NuTz now to do my own!

NBMWSsix

Thank you.
If you ever do and you have some questions feel free to call me and I will do my best to help you out.

[Packy]

Wow, that is awesome!

[2000 Tran Zam]

All i can say is wow. this is a good write up, since reading most service manuals are boring and not quite as precise with detailed pics of what you need. if i ever have a tranny problem, at least now i know i can have someone help me do it

[98 SNAKE EATER]

Added to favorites!!

Excellent writeup

[MIKE2000Z28]

I put gm Synchromesh in my car and the shifting got better? So your telling me, its gonna kill my tranny?

[NBMWSsix]

Originally posted by MIKE2000Z28
I put gm Synchromesh in my car and the shifting got better? So your telling me, its gonna kill my tranny?

Did you buy your car new? Are you the only owner? Where you live and the climate makes a difference. Warmer temps don't affect the shifting very much, and it may seem smoother for now. It also depends on how you drive it. If you drive it hard I see you needing a rebuild sooner. With synthetics the colder temps is where it will affect shifting more noticeably.

GM Synchromesh is safe choice for your tranny.

EDIT: I did some research and have updated the Q&A.



Clicky!

[eboggs_jkvl]

I have copied this thread into the How to forum. You may unsticky this thread. I am changing the links in the other thread to point to pictures on this site.


This is awsome!


Elmer

[NBMWSsix]

Originally posted by eboggs_jkvl
I have copied this thread into the How to forum. You may unsticky this thread. I am changing the links in the other thread to point to pictures on this site.


This is awsome!


Elmer

Thanks

I think it would be a good idea to leave the Q&A sticky though. We could remove the Tranny rebuild since it has been moved into the how to forum. But the Q&A would be good to leave since it has a lot of common questions answered related to this forum. Sound good?

[Sally 5.0!]

I'm very impressed.

Nice write-up.

[NBMWSsix]

Originally posted by BlackWS602
OMG this deserves a sticky.

Moved it. Just cleaning up things a bit.

[BeachZ]

Fantastic job! Props to u!

[NBMWSsix]

Originally posted by BeachZ
Fantastic job! Props to u!

thank you.

[racer88]

Nice, just took my B/F's T56 down to get it repaired. Broke a blocking ring to 3rd gear and well, it's toasty again. He said he was going to try it himself, he gave up.

Too bad I just found this now! Thanks for the info and pics, we may need it sometime again at a later date.

[NBMWSsix]

Thanks. If you need any help just let me know. You guys can PM me and we can talk and I will do my best to guide you should you decide to try it again.

[racer88]

Originally posted by NBMWSsix
Thanks. If you need any help just let me know. You guys can PM me and we can talk and I will do my best to guide you should you decide to try it again.

Thanks for the offer. I think the next time he's going to swap to a Turbo 400 he has. I think this is tranny repair #2 for this tranny it's the 2nd one. But maybe with mine should anything happen *crosses fingers* I have been fortunate that mine's been fine raced as much as it has but I am putting alot less power through mine.

[NBMWSsix]

Originally posted by racer88
Thanks for the offer. I think the next time he's going to swap to a Turbo 400 he has. I think this is tranny repair #2 for this tranny it's the 2nd one. But maybe with mine should anything happen *crosses fingers* I have been fortunate that mine's been fine raced as much as it has but I am putting alot less power through mine.

Power is rarely the culprit for a tranny failing. It's the other parts of the drivetrain that contribute to something going wrong.

[FastAl]

Very nice!

One question I have is on all the other guides pretty much all say you need a hydraulic press at least a 10 or 12 ton one?

I'm getting ready to rebuild my T56 since it doesn't like over 200 powershift 1/4 mile passes and pops out of third nearly everytime now and just sounds horrible

[NBMWSsix]

Originally posted by FastAl
Very nice!

One question I have is on all the other guides pretty much all say you need a hydraulic press at least a 10 or 12 ton one?

I'm getting ready to rebuild my T56 since it doesn't like over 200 powershift 1/4 mile passes and pops out of third nearly everytime now and just sounds horrible

Only need a press or similar if you are going to be replacing any bearings. My advice is do not touch them unless they are damaged or broken. They are a PITA to replace. All the other parts slide over them because they are the same diameter as the shaft they are on.


And thanks.

[Kal-El]

awesome, job armando i hope that mine will go just as smooth.

[NBMWSsix]

Originally posted by Kal-El
awesome, job armando i hope that mine will go just as smooth.

It will...

[VILeninDM]

Hey Armando,

I just recently came across your post. Nice job on that tranny.

I have my T56 fully disassembled in the garage right now. Still need to clean and replace things, but I am still not sure what to do about that end-play tool (p46 of the manual). Where did you get yours?

[NBMWSsix]

Originally posted by VILeninDM
Hey Armando,

I just recently came across your post. Nice job on that tranny.

I have my T56 fully disassembled in the garage right now. Still need to clean and replace things, but I am still not sure what to do about that end-play tool (p46 of the manual). Where did you get yours?

I didn't. Unless the play is excessive you will be fine.