T case repair or replace

I took my tranny and t-case to be inspected and it turns out myy D20 t-case has a hole and needs to be replaced so I started looking for just an empty case. Not having much luck in that department as everyone locally has them complete. When I add in the cost of the new t-case($350-450) that bumps the cost of the tranny/t-case rebuild to almost a grand. I was able to find a T-18/D20 combo locally for $500 which seems smarter than just getting the t-case. After using the google all day, I think i have it narrowed down to what will need for the T-14>T-18 swap. Without researching all the costs (new bell/adapters/ds mods) I started thinking that just replacing the t-case will be the easiest since it is bolt off/bolt on. After reading a lot of threads, most people rave about the T-18, and realizing a lot will depend on my usage (light off road/mostly highway dd) it seems i could go either way. I also have access to a D300 for the makings of the T-18/D300 combo which I understand is great for crawling. I guess I am looking for opinions on the cheapest/best way to go. Overall costs being equal, I am inclined to go T-18/D20 under the its better to have and not need theory. I do not know the specific application of the T-18 combo (ford, jeep etc.) Thanks for the input.

 

Without looking at tranny length it's hard for me to say but will there be a difference in driveshaft length? If so you have to factor that cost in as well.

A d20 t-case should be easy to find. Did you post something in the classifieds here on the board? I passed one up yesterday cause I just didn't need it. I'm sure there are some around. A t-18 is a great tranny, but if saving money is your goal I'd simply fix the 20 and be done with it.

What caused the hole in the 20? Can it be welded or otherwise repaired?

 

Personally, I'd buy the trans/tc combo, put the t/c in your Jeep, and be back on the road. then you can either sell the T18 & recoup some $$$, or just stick it in the corner of your garage in case you decide on a swap later.

 

If i understand the tranny guy correctly, a individual bearing worked loose and caused the damage. I will see it when i pick it up today. The drive shafts will have to be lengthened/shortened if ive read about the swap correctly. I looked in the classifieds before researching the swap, but was waiting to put a WTB until after this thread. I had not thought about buying the trans/t case and just not using the tranny.

 

Dana 20s are very plentiful, and you should be able to find a replacement locally. I suggest you keep looking for another D20 and change out yours.

Don't go to the wrecking yards - instead try the WTB (want to buy) forum on your local Jeep forums. Most (all?) areas of the country have their own 4x4/Jeep forums with plenty of participation.

Used parts are always cheapest if you can find them private-party. You can also check the local Craig's list for parts, though I think you'll do better at a Jeep forum.

Also, if you can do a T-18 swap for $1000, you're doing really well. The only way to do the T-18 cheaply (ie less than, say, $1500) is to find a Jeep or IH T-18 that has already been converted to a transfer case. This swap has been covered a lot here... and if you want to do the swap cheaply, I think you'll need some time to gather parts. Plus the changes to the body to accommodate the taller T-18 are not insignificant. This swap is manageable for a good amateur, but involves some work and fabrication.

 

The local jeep specialist wants $450 for his in used condition. On CL i found a guy w/a D20 for $300 or i can get the T-18/D20 combo for $500. I have been able to find them on ebay in the 125-150 range, but at 90 lbs i think shipping would be a killer. I will look at the forums and see whats available, but unless its within driving distance, i figure the 18/20 combo seems like the better deal because im getting a T-18 for less than the price of a D20. I have a few feelers out to the local jeep club and the tranny shop gave me a possible source. I know that D20's were in different set ups, but if all i need is the housing it shouldn't matter which application it came from, right? Thanks for the help.

 

Which Jeep vehicle did the T18/D20 come out of? They are not all the same, and some will work better than others. $500 would be a great deal if it's from a '77-79 CJ, just fair otherwise.

I'd expect to spend less than $50 for a D20 in a private party sale. There were a lot of them made, and they aren't particularly desirable. The low range gearing isn't very good, and the output housings break in heavy service. Nobody wants them except for replacement parts.

Yes, any case should work.

 

Another thing about the t18, there is two version of it. The only difference is the ratio on 1rst gear. Early t18 have around 4to 1 ratio and later t18 have 6.32 to 1 ratio so it would be preferable for crawling. There a easy to difference them. The earlier t18 have the reverse speed at the top right of the tran, and the later with the big ratio got is reverse a the bottum right. There is another way to identify the tran but i'm not use to it. Personnaly i run a t18 with the 6.32/1 ratio and i find it very nice for off road application. But i talk with a few guy who have a t15 and they like the fact that 1 rts gear and reverse are both at complety left of the shift patern. That's not bad when you're mudding because is easier to shift from forward to reverse.

 

Right idea, wrong specifics.

The T-18 came in two different ratios, close ratio and wide ratio. The CR transmissions were used in CJs and Commandos from '71 through '76. All other T18s are WR. Lacking any tags or knowledge of the donor, you must count the teeth on the input gear to identify the CR transmission. (I have the tooth counts at home in my notes - later if needed. Nick knows them off the top of his head - search for his old posts about the T18).

The shift pattern only has to do with age. T18s from before about 1978 have reverse next the 3rd gear. Later transmissions have reverse next to 4th.

 

D20's are fairly common here, I have seen several on craigs list locally, I got one off an Scout for $50. Beside Jeeps they were in Scouts and Broncos.

 

Wide ratio T-18's are 6.32-1 and have a 17 tooth input gear. Close ratio units are 4.02-1 first and have a 23 tooth input gear.
There were some Scout T-18's that were close ratio but are anything but common. I think they may have been special optioned or something. Run into a couple of them over the years.

Bronco 20's won't work with a Jeep or Scout T-18. Bolt pattern is way different, front output on wrong side, etc. The Scout 20 works quite well. Just make sure you use the correct input gear as there were two different pitch's of the teeth on the input gear depending on what gear set used in the Scout. Both were 2.03-1 low range.

 

I appreciate all the input. I've beensearching CL hopin to find somebody with just the housing but no luck so far. I havent looked up by ABQ yet although I did read the CL listing for the 304 one of the members had up (larry d???) I have some time to find one since my frame is off for blasting and crack repair. I don't have pictures, but appearantly what happened is that a bearing from the tranny broke loose, worked itself through the t-case, and beat the housing so much that it broke the right side of the casting from the top to the metal cover. So if I have all the info right, If I go the T-18 route, I want one from a '76-'79 CJ with the wide ratio. Any thoughts on switching to the D300 t-case? Is it adaptable to the T-14 or would I need a new tranny? On the upside, the thing that started this whole tear down (ring gear/turning flywheel) is done. Thanks.

 

you would have to buy adapter... best bet buy t176 4speed with dana300 already with it.

 

That version would work well, but it's scarce. The most common seems to be the T-18 from a V8 J-truck or Wagoneer, which has a very long input shaft. You can convert these to a short Ford input shaft, get a T-150 or T-176 Jeep bell housing, and put it all together. The close-ratio transmissions from 1972-76 would also be an easy swap, but would not give you the most gear reduction ... still a worthwhile swap. Plus the floor panels from a 72-75 will make your swap a lot easier.

Lots of ways to go here.

This topic has been covered a lot in earlier posts. Search for Nick's (nickmil) old posts on the T-18.

The Dana 300 will not bolt up to the T-14, except for some rare D300s from one year of Scout (and the word is out about these - expensive if you can find one). If you want a D300, you can use any of the truck 4-speeds and buy an adapter kit to the Dana 300. The D300 will give you better low range ratios, and can accommodate Tera gears with a much better 4:1 reduction. That would give you a really high crawl ratio, but would not be cheap.

I think you'll get the most reduction for the least money by working out some combination of a Jeep/IHC WR T-18 and the Dana 20.

 

I think i have a good understanding of my options, and just have to search them out. Thanks for the input.

 

a lead for you sent via pm.