Who has rebuilt T90 transmission?

Hey all,
I have a working T90 but it's leaking, a little noisy and pops out of 2nd. The Novak rebuild kit is out of stock for some time now...at some point I do want to make an attempt to rebuild it but still sketchy about it. Anyone who has tried it either very experienced or first timers have any advice? How did it go? Special tools? Problems? Etc?

Thanks all...Jeep On!

 

I'm not quite there on my Jeep but, this document has been referenced on the site a whole bunch. I've read it a couple times, and it seems to be the most thorough document I've found relating to rebuilding the T-90.

https://willysoverland.files.wordpress.com/2012/03/t-90-rebuild-guide.pdf

There are others that i'm sure will be glad to impart their knowledge as well!

 

Popping out of second gear is usually caused by the second speed gear bushing being worn, the 2-3 synchronizer teeth and second gear engagement teeth being worn, input and output bearings and input to mainshaft pilot bearings being worn, or a combination thereof.

 

Listen to nickmil, I rebuilt many back in the '70s. and it is one of the most simple transmisions to rebuild, If you can find the good OEM parts now, you are way ahead.

 

Special tools besides the various rods and conduit spacers when loading the zillion roller bearings? Appears i may need a press for tHe bearings removal and install?

 

Really, all you need is a press to do the bearing on the input shaft, otherwise we have done all the rest with broon handles and Vasolene, sometimes a closet rod for a transfer case bearing set up as a dummy shaft.
I hope you have a FSM, how many times has this been said?
I've spent a lot of time stuffing roller bearings in transmissions and T cases. I used to do do this for a living but it's been a few years ago and I still say is to follow what nickmil and others tell you do, they are still doing the work.
I still have soft spot in my heart for the 198s.

 

I did mine pre internet in my back yard. No special tools just a bit of resourcefulness. i had never done one before and that one was full of water at some time. All i had was the reproduction FSM and some guys at the local 4x4 shop who were old jeep guys. (Iron springs 4x4).

One thing i did was use wheel bearing grease to stick the needle bearings and spacers into the thing. That is apparently very wrong. I have read that the wheel bearing grease does not dissolve as readily as vaseline and can cause failure. I did not have issue, but maybe I was just lucky.

Anyway, I rebuilt mine with no prior experience, just used the FSM and it worked really well.

 

A properly sized dowel rod works wonders for the roller bearings. Also, I've just started using this stuff for trans assembly....works MUCH better than Vaseline or bearing grease.

http://www.lubegard.com/~/C-292/Dr.+Tranny+Assemblee+Goo

 

I am putting a t90A gear set from a truck with the 10 spline and 1 1/8 diameter into a t86 case
There are several things that you must have on hand before you start, 100 shop rags and 4 16 ounce cans of penetration oil.

Special tool 9 inch brass drift= 8 inch 3/8ths extension and a deep well 3/8ths drive socket.

The transfer case has a standard foundry mark that reads 18-15-18 W G DIV on rear facing center. Just below that is a less readable mark that reads 12A-4 OR less likely 12-42. Remove the cover plates 5 bolts, (my cover plate had the letter P in reverse stamped in it) if the bolts are tight and the star washers are missing someone MAY have been in there before you.

Remove the 5 bolts, pull the 1/8 inch cotter pin, use a 12 point 1 5/16 inch socket on the castle nut, (IF THE CASTLE NUT HAS CUTS IN ITS CASTLES THEN SOMEONE MAY HAVE BEEN IN THERE WITHOUT A PROPER SOCKET), remove the washer and the gear. There is no number on the castle nut or washer. There is a number on the rear face of the gear 18-8-23 and a capital W inside of a circle. The bearing has a number on the rear facing face reads NEW DEPARTURE 3307 MADE IN USA
When you pull the gear set out to the rear the paper gasket will tear, save this pattern.
Wrap the main gear cluster in a shop rag for now, NOW.

ON STEP 2O. The author said to tap the main shaft to the rear too far, WARNING...what he forgets to write is to remove the key first. the key measures .62 thick rectangular (ISH) 1.4 wide with one edge at .893 and the other edge it measures .787.

The reverse gear orientation on the other shorter shaft use the 6 inch C clamp idea FOR REMOVAL.
The reverse gear measures 1.89 thick across the smooth faces. The gear width is .74 at the bottom of the gear face. My outer dimension of the gear is now 2.23 but it has some wear so it probably started at 2.25 For the inner dimension of the gear face is 1.738. For the Inner dimension there is a brass type material with a circular like grove and dots imprinted in it from front to back that dimension. This is the oiler for that gear. On the faces to the gear fins there are two lengths .28 goes to the front .111 to the rear.

 

I rebuilt mine using a Herm kit. I have no previous experience. With the rebuild guide that is easily found through a search engine, it was very straight forward.

 

I used Herm's kit also.

 

J C Whitney had the t 90 kit for $75 on ebay

 

I know after you are done clean the end of your cluster gear shaft and put a dab of sealer on the ends. I done mine , it is as simple as they get. After I put it back in I had a leak between the bell housing and the trans. It took me three time to find it, I finally put it together, put the oil in it, set it in the sun and watched it and saw the oil coming out of the end of the cluster gear shaft, brake clean and a dab of sealer and Bingo, fixed. Good luck