T14 and D18 Rebuild Kits

My drive train is currently out of the jeep and was thinking it may be a good time to rebuild the notorious leaking D18 and T14. The last run with the combo did not show any signs of needing a rebuild but there are a lot of good threads here and write ups on the net so I may try to tackle the rebuild.

Few questions:
Should I do a complete rebuild, bearings and all, or just replace the seals?
There are serveral rebuild kits on the net including Novak, Krage and others. In regards to the quality of the kits, is there one better than the others?

 

Well, I just recently rebuilt my T90/D18 with the help of Sparky and the follow along directions I found around here somewhere. I won't say that it was really easy, but it wasn't as complex or difficult as I thought it would be. Actually, getting the whole thing back in the Jeep was harder then rebuilding the T90. I pretty much just called Herm the Overdrive Guy, told him what I wanted to do, he asked me a couple of questions and several days later I had everything I needed to rebuild.

Hope this helps some. If you have specific questions, post or PM me. I'll let you know exactly how I went about the rebuild.

Dondo

 

did you get alot of metal (other than brass) in the oil?

 

Transmission: if you don't have any broken parts, you can either replace the blocking rings and seals, add the small parts kit (needles, snap rings and thrust washers), or add the main bearings for a "complete" rebuild. Pretty much the same for the TC, except no blocking rings. You'll need a dial indicator to reassemble if you replace internal parts in the TC.

No personal experience, but I recall reading that the Novak kits are the best. Herm's kits are equal to Novak's except he picks quality import bearings to replace Novak's USA-made bearings. I think all the mass-market sellers offer an Omix-Ada kit with the cheapest bearings available. If you call Herm, ask him. He has a reputation as an honest and helpful guy, and knows these issues backwards and forwards.

 

The t14's main problem is bearings. if you have a howl in the transmission that goes away when shifted into 3rd the bearings need attention. I bought my kit from 4wd, but I did it 12 years ago or so. Back then they still came with Timken and/or Federal Mogul bearings. If you do rebuild the t14 pay very close attention to the front bearing retainer gasket and trim it as needed.

 

I was in the same boat. I was going to rebuild my t14 as well. Looking at everything with the top cover removed looked fine to my un-trained eye. I ended up have Herm the Overdrive Guy rebuild both my T14 & D18. On my tranny, the input shaft, main shaft, 1st gear & reverse all replaced along with bearing, ect. When I puck up my tranny & transfer case Herm had all my parts that he replaced, explained why the needed replacement. Total of the rebuilds cost me $605, which feel was more than far, and less expensive I feel in the long run.

 

Thanks for all the great info....

I have had no noises from the transmission and have not gotten them drained to look for metal shavings...

I bought a dial indicator and magnet base today from Harbor Freight... Totalling $13.00

I wish I lived around the corner from Herm.... $605 sounds good for both..... But I like the challenge and to tinker so doing it myself (if I don't mess it up) will be rewarding.

 

Uh... now I am confused...
Does the D18 have a castle nut on the intermediate shaft?

I am looking to order the Novak rebuild kit so I pulled the transfer case and went to measure the intermediate shaft…. On one side it has the locking “key” that holds it in and on the other side a castle nut. It measures just a hair over 1 ¼”. I don’t see any casting numbers to identify it and I want to make sure I know what I have before ordering the rebuild kit.

Thanks
PIC 1
PIC 2

 

Don't know what the castle nut is for, thats not normal. The shaft is held in with a flat piece of steel and the small bolt from the 1st picture, the shaft goes in 1 way only.

 

might be an AA tapered conversion kit on the int gear.

 

What is the Advance Adapter Tapered Conversion?

 

I presume tapered bearings means bearings like wheel bearings, instead of the loose roller bearings of the original int. shaft.

 

that's correct
but there has to be a way to tighten the assembly and set the preload on the bearings, hence the nut on the end.
it may not be AA, could be a home brew as well.

 

Thanks for all the great info....

Does anyone know of any docs or other info for specs?

I will pull it apart next weekend...

 

I agree with Jim, it looks like one of the old AA conversions. I'm going from memory here but IIRC the AA intermediate shaft had a larger head on the one end and the bolt/retainer held the shaft in place just like the stock style. The races were pressed into the intermediate gear that had to be machined for the conversion. There was a spacer that went through the intermediate gear and then shims that set the preload on the intermediate bearings. The nut on the other end held the tapered bearings tight against the shims and races. This is the way NP 205 transfer cases were built and how pre-load was set on those. I'm pretty sure AA emulated that design with their conversion......

 

I thought that these tapered kits were done by 4Wheel West. I believe that AA resold them for a while. They are not made anymore.

I would doubt homebrew, in that it would take a machine tool that was brutally rigid and some seriously hard tooling to machine the pocket for the tapered cups in the intermediate gear. I am sure that O'Brien made them up from green steel with said pockets, then had them hardened.

I installed one many years ago and it was a dud of an upgrade, in my book and I went back to the factory design. A hard intermediate shaft with good BCA needle bearings and the original thrust washer design is very good. But if yours is working alright, probably just great to leave well enough... alone.

Eric

 

What "tools" have people used for the D18 tear down?

I have seen the axe method... any other methods?

 

I got the TCase apart...