Justin93

So recently i ran into a wall with my current build leading me to change my direction with my Motor and Transmission.
Currently in my garage is my pre-86 Iron cast corvette block .060 freshly honed less than 2k miles on it. My T5 lies a mystery though, while it still had the stout '5th' over drive which was almost impossible to use - i decided if im going to be purchasing a 3-10k+ Engine setup i as might as well get a transmission to be able to utilize the powerband of the vehicle.

With that being said i need help and pointers of what to look for and the HAVE TO'S and DON'T DO'S of the T56 swap, everything from where i go to purchase it and what i should be looking for in the whole package of the T56 - more importantly how to tell if ITS A GOOD FIND! i dont want to have to rehaul a junker for 700-1200 then put another grand into it, i would of put a new one at that rate!

If anyone can please add to the list of what i will be needing for this swap please let me know i would like to have everything down before i start throwing $$$
Parts Needed

T56 6 speed
Fabricated Crossmember (spohn/bmr/umi cross members applicable?TQ ARM?)
T56 Bellhousing
T56 Shifter
T56 Flywheel for 1 Piece Rear Mainseal Crank
or Centerforce 2 Piece Rear Mainseal Flywheel - CTF-700107
T56 Clutch Disc
T56 Clutch Pressure Plate
T56 Sealed Master/Slave Cylinder
T56 Tranny to Bellhousing Bolts
T56 Pressure Plate to Flywheel Bolts
Shifter Bolts (I reused the T5 shifter bolts)
Transmission Tunnel Heat Boot/Bellows (I reused the T5 boot)
Bellhousing to Engine Block Bolts (I reused the T5 bolts)


Its going in my 91 Camaro RS 5.0 HO 4 Speed Auto w/OD 305cu TBI.

I read the t56 swap stickies but im still lacking knowledge i need to be confident in knowing what im searching for.

Anyone with a T56 and that has swapped them in if you can shed light of the process/materials - tools needed and any issues or struggle you went through during the process?

And am i doing something unnecessary as selling my T5 and buying a T56 in its place?..
I have no problem cutting out my floor board and am willing to take 3 hours to correctly configure/install the clutch assembly.

I know a good amount of everything that goes into a car EXCEPT the Transmission and i would love to hear from some Guru's and members with experience to shed some light on me

jmd

iTrader: (4)

Don't bother behind the 305.
Don't bother without 3.42 rear gears minimum.

If you're buying one, have a shifter with you. Shift into 1st and spin the trans. 2nd and spin. Etc. There should be some effort involved, but each gear should lock the input to the output at the expected ratio.
Take a 3/16 roll pin punch, remove the offset lever and pull the tailhousing to inspect the magnets. Broken synchro keys and general metal filth will show up on them.

Justin93

Im going with 3.54's in ford 9'' might sell and just settle for a 12 bolt due to the hassle

Im buying a turn key Crate engine (suggestions for smog legal POWER willing to spend a pretty penny on my power train)

I have my T5 and .060 over block already in my garage.

I have a manual shifter as well, but that was off my T5 - are you refferring to the plate or actual shifter that goes on the Transmission ?

I Understand checking through all the gears but internally im a little confused.

Maybe some pictures can clarify the 'offset lever' and the 'Tailhousing'..

Examples of what NOT to look for and what to look for would also be ideal (pictures)

I know its a little time consuming but i need to know what im looking at.

Im familiar with nearly every other part of a vehicle except the transmission and internals..

I do have a Roll Pin punch as well and have access to a large variety of tools, just need some more specifics on what to be stay away from and i know there's going to be parts i will most likely have to replace - i would just prefer the easier/accessable parts needed rather than the whole unit itself.

Thanks for the post JMD I always carry a note book and write all the experience/teachings from others, appreciate it!

jmd

iTrader: (4)

think 3.90

Bolt pattern for the T5 shifter is different. Have one for an F T56 if you're shopping for those.

Lever is right under the shifter. Google pictures; it's super easy to remove if you need to remove the rearmost aluminum casting (tailhousing)

The bearing just ahead of the VSS reluctor ring has an outer race that's in the tailhousing, held by a clip. The surface of that race is going to be similar to the other tapered bearings in the trans.

You could also pull the front cover pretty easily and look at things, but I don't know that you'll find a seller willing to proceed with that. That would let you look at 4th gear synchronization teeth, bearings & races and a little bit of 3rd and the synchro.

Justin93

3.90 for a daily driver?

I think 3.54 would be suitable for both street and Freeway, i also want to put 295 tires in the rear as well, i had another thread started in the wheels section regarding being able to put them in without modifications as another third gen owner had done it and had a vague article that it could be done.

As for the T56 Is there a specific model i should be looking at for swapping into my 91 RS ? Going to put a crate motor/9" all those goodies in it as well so i want to utilize that extra gear.

I think at this point i can't commit to buying a t56 part but good for future reference. just want to clear out any discrepancies between the T5 and T56 in comparison.
Rather if its a no contest or not i would like to know pros/cons and what to watch out for and more importantly the swap and what experiences and advice you can pass down.

Im looking forward to your responses and will be trying to get some pictures with highlights of what were talking about.
Shifter lever, Bearings, VSS reluctor ring thats in the tailhousing, behind the front cover, 4th gear teeth, bearing and races and would like to know the differences between seeing a problem and when everythings gravy, if that makes sense.

Transmissions are like labyrinth's to me, so any light shed will be very informative as it is appreciated.

Do you personally have a T56 ? and if so why did you go with the 95' T56? any particular reasoning on which year(s) are viable to your swap ?
Thanks

NagleMac

iTrader: (1)

An LTI T56 will bolt right up. To use an LS1 t56 you'll need a bellhousing (or bellhousing adapter). Torque arm wise, what i have is S&W subframe connectors which can be used with their torque arm to relocate it off the trans and onto the connectors. I like this because it keeps the strees off the tranny case.

krazeefewl

iTrader: (1)

NagleMac is right, if you plan on keeping with a SBC then go with an LT1 T56, if you do find a deal on an LS1 T56 keep in mind you will have to replace not only the bellhousing, but the front plate, and the input shaft as well. So unless it is a really good deal I would be looking for a 94-97 T56 from a camaro or trans am. I've heard of people having issues with the ones from 1993, but I forget what the issues were.

NagleMac

iTrader: (1)

I belive the ls1 t56's can take a little more torque but either way you'll want a t56 over a t5. The only t5 you would want is one with a g-force case. Those are good for 650hp. But the case also cost 1500.

jmd

iTrader: (4)

With a 94-up T56, yes.

My recommendation is to look up the recommended wheel width for a given tire size and stay within those widths.

Hard to beat the LT1 T56 for a SBC. 94-97 is the 2.66 first / .50 sixth and easiest to find parts for.

It's expensive. It's really nice when done.

One I have in a car is an LT1 trans. modded for mechanical linkage. Kind of a "to prove it can be done" project. It works with a third gen push clutch. Why I chose that one is I wanted to keep the same driveshaft length as the prior T5 (already had a nice aftermarket aluminum driveshaft) and the 700-R4 in my other car at the time (parts interchange between a backup car can come in handy.) But I had already done hydraulic clutch retrofit so there was no challenge in that.

Oddly enough, I saw another mechanical conversion LT1 T56 on Craigslist recently.

There is no torque capacity difference between a 97 LT1 T56 and a 98 LS1 T56.

The Gforce case is still under $500 last I checked. Gearsets are, of course, expensive.

NagleMac

iTrader: (1)

Yup you're right. it's the gear set and main shaft upgrades that are $1000+. But the only make a case for the ford t5 setup.

Dakota W.

Some of the 4th gens came with 3.73's from the factory. Compare the gear ratios of the t56 and t5 and you'll see why you want at least a 3.73.

jmd

iTrader: (4)

Gforce still has the gm Muncie pattern T5 case. Obviously it's one of the poorest advertised products in existence. That and Ford continued T5 use more broadly for years.

Justin93

For identifiying gearing, and transmission I will use randys calculators to find my appropriate gear set.
http://www.ringpinion.com/Calculator...x#Transmission
and
http://www.ringpinion.com/Calculators/Calc_GR.aspx
to identify which is the most suitable gears.

So if there's no difference in torque capacity is the lt1 just a direct bolt up as oppose to the ls1's ? nothing about the ls1's t56 being a better transmission or internals?..

Im a little less educated in the transmission department but how do you identify the transmission gearing ? and how is it correlated to the gearing of the axle ?

Might be a broad question but any information would be alot of help as i want to know the best possible purchase of a t56 for my crate motor that i plan on having built 400 HP minimum (have my moser 9" too, detroit true trac diff and 31 spline axles to match)
After i learn how to identify the ideal Transmission for my application and purchase one, i will install the transmission and motor then have to take measurements for IEDLS.com to mate a custom drive shaft for the trans to my rear end.

So i would like to get up to pace with transmission specs and maybe if we can start with some need to know's so i can begin to grasp the concept and everything that goes into it and how it operates.

Im still learning so i am the pupil in this thread and am open to criticism and advice/suggestions as its my goal to learn not argue/differ in this thread.

Thanks everyone, just updating the thread title it should be: T56 Swap Suggestions HELP! lol

I don't want to have a crudely assembled transmission and don't mind dropping a pretty penny (2k?) on an equally reliable/and outperforming transmission, i mean im already getting a crate motor and have a moser 9" and getting a custom DS so at this point i want to do it right the first time and could use a good kick in the rear as to what to look for, at this point though i will not look at the 93' t56's just as a precaution to avoid any possible issues.

what to look for in a used 94-97 T56 ?
what to look for in a rebuilt 94-97 T56 ?
How to identify gearing and its importance in correlation to the rest of the power train of the vehicle.

Thanks again for all the replies and info, hope to hear back from you guys soon.

jmd

iTrader: (4)

Gears are a matter of opinion, but:

I suggest 3.90 gears based on having driven the 2.66 / .50 ratio T56 with gears from 3.23 up to 4.30. And various other gear experiences with GM transmissions over the years.

The LT1 T56 has a unique input shaft length, throwout bearing sleeve, clutch fork, and front plate. The 93 has no CAGS solenoid in the main case. So you can assume a pull clutch style F-body T56 with CAGS is a 94-97 unit. Just like anything, that doesn't mean someone couldn't rebuild a 93 unit with 94 case or some other oddball setup.