T86aa Transmission Problems

Rebuilt this transmission 4 yrs ago and it has been sitting ever since. started to drive the jeep around a little and shifter would not stay in first, thought it was shift forks not straight but no such luck. transmission now has a loud intermittent clunk in first gear, something catching or loose. Took the top off, but could not see anything obvioulsy. the rebuild kit was from novac, but apparently I made an error in the rebuild although the instruction were detailed and i thought i followed them.
Going to have to pull and take a look.
MY QUESTION : do you experts think it is something that can be fixed without a complete rebuild or is a rebuild in order. Any ideas on what it might be?

thanks

 

If you had a problem in assembly, about the only thing you can fix with the transmission in the car is if you 1) put the shift top together wrong, or 2) did not align the shift forks with the shift hubs. Pretty much everything else - the transmission comes out and is taken apart on the bench. Fortunately, removing a transmission from a Jeep is quite easy.

Does the transmission shift into second and between second and third smoothly, and not make noise? You probably put something together wrong, like installed the 1-R hub backwards. Can you shift into and out of reverse normally? When the transmission pops out of gear, it's usually because the parts are so worn that the side thrust on acceleration or decelleration pushes the gears apart, or because the gear is not completely engaging (left-out parts? improperly installed parts?)

 

Transmission shifts into all gears ok or it did before i messed with forks.. when i carefully remove the top without moving any internal parts with the forks the the top gear still has 1/8 of an inch or so to go to be fully engaged. dont believe gears are worn enough to cause side thrust. I will take a picture of with cover off and post. I probabably need to rebuild my top with new forks because I tried ti bend them a little and now they are somewhat misaligned.
I will have to remove transfer case with trans correct??

 

You can bring them down one at a time. Be sure to support the back of the engine. Disconnect the transfer case from the cross member, put your jack under the bell housing, and raise it until the weight is off the cross member. Then bring down the cross member, transfer case, and transmission.

 

Picture. I don't see anything obvious. could be tooth broken off on countershaft gear

 

Got the transmission and transfercase out today.

This picture shows how I bolted a 2 by 8 to the transmission bottom where the mount bolted on. I pushed the 2 by 8 over under the the transfer case before i located and drilled the hole in the board. Doing this made a perfectly flat (parallel to floor) place my jack. Th bolt holds the board sturdy to the trans. I then guessed the location of the "center of gravity" for good balance on the jack.



This idea really worked well. Trans pulled out of motor and was perfectly balanced and stable on jack.

 

the picture above shows that u can see a portion the main shaft pilot rollers. should not see theses correct??

Still having an issue with posting pictures, not intuitive. I screw it up every time . i have looked at directions several times, but i'm missing something. could someone post a STEP BY STEP procedure of how to post full size pictures with text attached to each. dont assume I know how to do a certain step.

thks for ur patience

 

This morning I disassembled ny T86 transmission, but didn't find anything obviously wrong. No metal in case , no broken parts, all gears, bearing, etc looked good, and I carefully reviewed all the T86 diagrams to check for parts errors, found nothing that shouldn't be there or missing anything. I did notice the 2nd / 3rd synconizere to slide rough and wash hard to move by hand. no visual issues with it. I reasmbled the main shaft with parts and put the cover and shifter back on. it seemed to shift 1st, 2nd good but again 3rd gear a little rough. I didn't disassemble the sync asm because i didn't have the correct snap ring tool to get the snap ring off. will do that tomorrow. right now at a loss for path foward. I guess it could be some other thing, but I elimanated the drive shafts and differentials. maybe throw out bearing, transfer case??
Looking for some help here
My wonderful wife brought lunch to the shop, but I have stopped for today to watch the nascar race. I would post oither pictures, maybe, but there is nothing to look at.

 

Maybe found a problem with T86. Syncronizer (2ND AND 3RD) HUBS ARE PRETTY SLOPPY. Not sure how snug they should be, but they have quite a bit of play in them when put together with out springs and the 3 dogs. Any comments on this. Thanks

 

What do you mean sloppy? Loose on the shaft or loose side to side?

 

snug on shaft, inner hub to outer hub. so side to side

 

timgr,
i have attached 2 pictures for further review. one shows the sloppyness between the inner hub and outer hub of syncronizer. u can see the inner hub "leaning" to the right in the outer hub indicating the large clearance.
the second picture is something i just discovered, that is the chipped teeth on the reverse idler gear. I didn't notice this before because my focus was on the 2 main shafts in the box. There is something about these chipped teeth that really caught my attention. Do you conclude the same issue as i did???????

 

I don't have one to compare it with, but the sleeve fitting loosely on the hub does not seem like a problem to me. The plates are spring loaded and are meant to hold the sleeve away from the hub.

To me, chips on that reverse idler are too severe. I would not use it.

From your description, I was thinking more about the end play of the hub. Often your small parts kit contains a lot of different snap rings, and you don't want to pick the wrong ones. There's no explicit description of adjusting the end play with snap ring thickness in the manual ... but I would certainly use the same thickness of rings I took out.

 

timgr,
the chips on the idler gear are on the wrong side. i think (trying to confirm) the gear goes in with the longer inner hub towards the front and if that is the case this gear was in backwards and clashed with the sliding gear.I dont recall those chips when i rebuilt trans a few years ago or i would of dressed them. being in backwards would move the gear too far forward which could of caused the first gear noise and coming out of gear. your thoughts?? i said i didn't find any metal in case but I didn't check the tub where i drained the oil out. i will check after supper. thanks for your thoughts.

 

here it is Glenn,

 

This all seems probable to me but, I would think it would have been VERY noisy and there would be lots of metal inside. If that's the case, and the transmission was driven for any length of time, I would be concerned about damage to the bearings from metal in the oil. At the very least, everything inside should be thoroughly cleaned and inspected before assembly.