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Wanting t-18a

Wanting t-18a

Dan77CJ7

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Denver,303Local
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76' CJ-7 4.2L/T-18/d20 d30sua/amc20soa M/T MTZp3 35/12.50/15s mc2100
I found this t-18a and Dana 20 from a FSJ, can anyone tell if this is what i need i realize its a photo, can i keep my Dana 20 and use this T-18 with it?

T-18 Transmission (6.32:1 Low Gear) from a FSJ.
It has Transfer Case bull gear attached and is ready to bolt to a Dana Transfer Case .
Includes Dana 20 Transfer Case and the short input shaft for conversion to short wheel base Jeeps.

thanks guys,
 
You want a T-18 from a CJ, the FSJ has a much longer input shaft. Confusing, yes! The FSJ can be converted. T-18 's have to come from a CJ to easily drop in a CJ. The favorite and easily adaptable Transmission comes from a Ford. Advanced and NOVAK have adaptor kits for the Ford T-18 , I did it in my garage with the few tools I had at the time and it went together fairly easily.
 
I found this t-18a and Dana 20 from a FSJ, can anyone tell if this is what i need i realize its a photo, can i keep my Dana 20 and use this T-18 with it?

T-18 Transmission (6.32:1 Low Gear) from a FSJ.
It has Transfer Case bull gear attached and is ready to bolt to a Dana Transfer Case .
Includes Dana 20 Transfer Case and the short input shaft for conversion to short wheel base Jeeps.

thanks guys,
:)
You have not yet said what it is going into...........that's almost as important as knowing what Transmission you have.........some input shafts will interchange and other will not...........these early T-98 / T-18 's are a :dung: shoot to get to work in a short wheelbase CJ.........get all the numbers off of it pull the top cover to check how many teeth are on the input shaft gear inside and call Novak and prepare to get educated.

:D:D:D:D
 
It looks like you have all the big parts. Note the long front shaft. Normally on the FSJ T-18 there is an adaptor present (not all front adaptors are the same length) to push the Transmission back far enough for the shifter to miss hitting the dash. The adaptor is not present in the picture so I assume the PO pulled it to prep for the CJ short shaft. That short shaft is worth about $250. The stick out of the front shaft for a CJ T-18 is 7.43”. The Ford version is shorter at about 6.5” and requires a special pilot bushing (about $80 or so) to make up for the shorter length.

The good news is that from 1972 through 1979 CJs had a T-18 as a factory option but the important years in this case are 1977 to 1979. During those years the bell housings were drilled and tapped for both the non-adaptor (CJ) T-18 and the Ford version as the stock T-150 uses the same Ford “butterfly” pattern. Drilling for both patterns made assembly less complicated. The T-18 was only available behind the I-6 in a CJ until 1979 when it could be ordered behind the AMC 304 . Unfortunately 1979 was the last year for a T-18 in a CJ as well. The 1977 to 1979 skid plate is set up for the T-18 Transmission mount and the frame is ready to go too. For the T-18 the back skid plate holes line up with the last set of holes in the frame for the skid plate to leaving the front holes empty. The Skid plate also needs to be dropped about 7/8” and the torque bracket for the T-18 is a little heavier. (Thicker, about ¼”)

There are a few other things too. The CJ T-18 has one bolt, top drivers side at the clutch fork, which has the head (special head to keep it from turning inside the bell housing) of the bolt on the inside of the bell housing rather than the bolting through the transmissions into the housing. The fork is notched for the head as well. Both the special bolt and the notched fork are no longer available so if you don’t have either take a bolt and add a little weld to the side so that the nub will catch the side of the bell housing to prevent it from turning when the nut is tightened then grind the head down to keep it from interfering with the fork. The fork will need to be notched too; you have to play with it until it is right. The clutch system its self is the same between the T-150 and the T-18 .

The other issue is the fact that the Dana 20 Transfer Case linkage for the T-18 is about 4” longer than the T-150 . The best options are to either use the Dana 20 that was bolted to the T-18 or at least take the linkage from the donor Dana 20 if possible and swap it to the Dana 20 you have.

It’s late and I’m sure I forgot something but this should get the conversation started.
 
:)
You have not yet said what it is going into...........that's almost as important as knowing what Transmission you have.........some input shafts will interchange and other will not...........these early T-98 / T-18 's are a :dung: shoot to get to work in a short wheelbase CJ.........get all the numbers off of it pull the top cover to check how many teeth are on the input shaft gear inside and call Novak and prepare to get educated.

:D:D:D:D

its going into my Batmoblie........:p
 
It looks like you have all the big parts. Note the long front shaft. Normally on the FSJ T-18 there is an adaptor present (not all front adaptors are the same length) to push the Transmission back far enough for the shifter to miss hitting the dash. The adaptor is not present in the picture so I assume the PO pulled it to prep for the CJ short shaft. That short shaft is worth about $250. The stick out of the front shaft for a CJ T-18 is 7.43”. The Ford version is shorter at about 6.5” and requires a special pilot bushing (about $80 or so) to make up for the shorter length.

The good news is that from 1972 through 1979 CJs had a T-18 as a factory option but the important years in this case are 1977 to 1979. During those years the bell housings were drilled and tapped for both the non-adaptor (CJ) T-18 and the Ford version as the stock T-150 uses the same Ford “butterfly” pattern. Drilling for both patterns made assembly less complicated. The T-18 was only available behind the I-6 in a CJ until 1979 when it could be ordered behind the AMC 304 . Unfortunately 1979 was the last year for a T-18 in a CJ as well. The 1977 to 1979 skid plate is set up for the T-18 Transmission mount and the frame is ready to go too. For the T-18 the back skid plate holes line up with the last set of holes in the frame for the skid plate to leaving the front holes empty. The Skid plate also needs to be dropped about 7/8” and the torque bracket for the T-18 is a little heavier. (Thicker, about ¼”)

There are a few other things too. The CJ T-18 has one bolt, top drivers side at the clutch fork, which has the head (special head to keep it from turning inside the bell housing) of the bolt on the inside of the bell housing rather than the bolting through the transmissions into the housing. The fork is notched for the head as well. Both the special bolt and the notched fork are no longer available so if you don’t have either take a bolt and add a little weld to the side so that the nub will catch the side of the bell housing to prevent it from turning when the nut is tightened then grind the head down to keep it from interfering with the fork. The fork will need to be notched too; you have to play with it until it is right. The clutch system its self is the same between the T-150 and the T-18 .

The other issue is the fact that the Dana 20 Transfer Case linkage for the T-18 is about 4” longer than the T-150 . The best options are to either use the Dana 20 that was bolted to the T-18 or at least take the linkage from the donor Dana 20 if possible and swap it to the Dana 20 you have.

It’s late and I’m sure I forgot something but this should get the conversation started.

thanks saddle. i think ill buy the parts and wait on the swap i'd like to rebuild the T-18 and low gear the Dana 20 . so i'll need to sell a kidney first!:chug:
 
The T-18 and a low geared Transfer Case with reasonably tall gears in the pumpkins is a good way to go but always make sure you have ALL of the parts needed for a swap before you start to unbutton a running jeep or you will end up with a non-mobile catch all in the middle of the garage for an extended period of time. I’m just saying…….
 
The T-18 and a low geared Transfer Case with reasonably tall gears in the pumpkins is a good way to go but always make sure you have ALL of the parts needed for a swap before you start to unbutton a running jeep or you will end up with a non-mobile catch all in the middle of the garage for an extended period of time. I’m just saying…….

i leaned that many years ago when i tore apart my 63 Fairlane SC/HT only got it just running again after 5 years.

when i do the swap it will be a completed weekend project with all the right parts and you guys,:chug::chug:


what would my 4low be compared to if i were to keep the Dana 20 guts and have the granny gear? would it be like my T-150 /Dana 20 with low kit?:confused:
i only ask because i just had the T-150 rubuilt....I know, I know, i panic when Gomer would run so i rushed her to the Transmission shop like it was the ER!!!
 
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Dan to best calculate your overall gear ratio could you list the rear gear ratio? The info I have states that the T-150 has a 2.99 1st gear, Dana 20 at 2 to 1, Dana 20 with low gear kit 3.15 to one, So you can do the math. Doing this operation in one weekend ain't gonna happen, I have seen the pros do it in a day though. If it has the short shaft at the tranny it might require a clutch disk swap and pilot bearing also.
 
Dan to best calculate your overall gear ratio could you list the rear gear ratio? The info I have states that the T-150 has a 2.99 1st gear, Dana 20 at 2 to 1, Dana 20 with low gear kit 3.15 to one, So you can do the math. Doing this operation in one weekend ain't gonna happen, I have seen the pros do it in a day though. If it has the short shaft at the tranny it might require a clutch disk swap and pilot bearing also.

I have 4.10s and will keep that ratio. im thinking i'll wait untell i can locate 77-79 CJ T-18 what would you suggest i look for in a T-18 torx? and i can do this in a weekend....:cool: i plan on only doing the install and the tricky stuff the pros can over charge me for :D

thanks.
 
The way I see it, the things you need to consider 1st is the correct input spline count, length, and pilot bearing size, so a new clutch disc with correct spline count and input bearing could be required here. The inside of the bell housing has more drilling hole locations if you need to drill and tap for different hole locations. Not sure how the driveshaft lengths will work out. A new body shifter cover will need to be made, but that is simple out of a piece of sheet metal, tin snips, and drill the holes. Not sure how the rear Transmission mount up, so maybe a bit of drilling for the hole locations here. Since you are using a modified fsj tranny and Transfer Case that could make things a bit different. So I would suggest taking a few measurements to make sure everything will fit correctly. It will give you almost an 82 to 1 low gear ratio, with the low gear kit, so that's pretty good crawling there.
 
As far as doing the job in a weekend I think that technically it is plausible as no outside adaptors, hacking or whacking are required (1977 to 1979) with the exception of using a Ford T-18 over a CJ version where the special pilot busing and rear adaptor/shaft kit are needed but that would assume you have the T-18 drive lines as the T-150 ones will not fit with the T-18 . Two options, have a driveline shop shorten the rear and lengthen the front or order new ones. Either way it is best to get a measurement after everything is in place with the jeep on the floor. The bottom line is this job can be done using all original OEM parts; there are no tricky parts to pay others to do later.

Let’s look at crawl ratio. You have a T-150 with 2.99 low X 2.0 Dana 20 Transfer Case X 4.10 axle gearing = 24.52 crawl ratio which is pretty crappy. Change that to a 3.15 low kit in the Transfer Case : 2.99 X 3.15 X 4.10 = 38.62. Better but still boarder line for crawling in my opinion. Of course a lot also depends upon tile size too but these numbers at least give you some idea of where things are at.

With a wide ratio T-18 the math works out as 6.32 X 2 X 4.10 = 51.82 which is twice as deep as the stock set up you currently have. By adding the low kit in the Transfer Case : 6.32 X 3.15 X 4.10 = 81.62, over 3 times a deep as stock. Again crawl ratio is only a guide but to me 50 is about where crawling capability starts and 80 + is great.

However what you decide to do with gearing has a lot to do with what you plan to do with the jeep; too low a crawl ratio can sometimes do more harm than good in the mud and sand.
 
Just to elaborate on what Saddle Tramp stated before.........The T-18a was only offered in CJ-s in 1978 and 1979. They T-18 was offered in CJ's from 1972 to 1977 in the CJ and was a "semi-granny" 4-speed with a non-synchronized 4:1 1st gear ratio. They have a reverse up and to the right shift pattern. The T-18a had a 6.32:1 1st gear ratio and have a reverse down & to the right shift pattern.

The T-18 & T18a was offered only behind the 6-cylinder engines in the CJ5 's..........don't know why; they hadn't plenty of strength to handle the V-8. The T-18 & T18a was offered behind the AMC 258 i6 / 4.2l and the AMC 304 in the CJ7 . I sold a T-18a out of a 1979 CJ7 with a Dana 20 , the bellhousing, the driveshafts, shid plate and everything for $600 a few years ago. Probably could have gotten more money if i would have held out longer.
 
Just to elaborate on what Saddle Tramp stated before.........The T-18a was only offered in CJ-s in 1978 and 1979. They T-18 was offered in CJ's from 1972 to 1977 in the CJ and was a "semi-granny" 4-speed with a non-synchronized 4:1 1st gear ratio. They have a reverse up and to the right shift pattern. The T-18a had a 6.32:1 1st gear ratio and have a reverse down & to the right shift pattern.

The T-18 & T18a was offered only behind the 6-cylinder engines in the CJ5 's..........don't know why; they hadn't plenty of strength to handle the V-8. The T-18 & T18a was offered behind the AMC 258 i6 / 4.2l and the AMC 304 in the CJ7 . I sold a T-18a out of a 1979 CJ7 with a Dana 20 , the bellhousing, the driveshafts, shid plate and everything for $600 a few years ago. Probably could have gotten more money if i would have held out longer.


Colorado-

A little clarification: There are two low gear ratios for the CJ T-18 transmissions , 4.0:1 and 6.32:1 and are commonly referred to as “close ratio” and wide ratio” respectively. Starting in 1972 until sometime during the 1976 model year the transmissions were all close ratios (4.0:1) and then switched to the wide ratio version (6.32:1) but no one seems to know exactly when the change happened during that year. Bell housings prior to the 1977 model year were all Transmission specific (T-14 , T-15 , or T-18 ) but in 1977 through 1979 the bell housings were drilled and tapped for both the standard Transmission (T-150 , Ford “butterfly” pattern) and the CJ T-18 . All T18s have an unsynchronized low gear; the T19 is basically the same Transmission as the T-18 but with a synchronized low gear. The 1978 and older T18s have the reverse gear position to the right and up by 3rd fear, 1979 is to the right and down by 4th gear. Jeep only offered the T-18 as a factory option behind the I-6 in all model years except for 1979 when it was available behind both the AMC 258 i6 / 4.2l and the AMC 304 and in either the 5 or 7, it didn’t matter. :chug:
 
Sadlle tramp -

I certainly don't want to start an ruckus, but I have a 1976 Jeep CJ7 Renegade with 35,000 miles on it. It is completely stock and has the AMC 304 with T -18 behind it. We have owned it for 15 years and bought it from the original owners. It has never been modified since it left the factory. I have also owned a 1977 and 1978 CJ7 with a AMC 304 V-8 and the T-18 .


renegade.jpg


I also have an AMC Jeep sales brochure from 1976 that clearly demonstrates that you could order a CJ7 with the AMC 304 V-8 and the T-18 . They were not very common, but they are out there. I'll try to find it and scan the page in.
 
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Sadlle tramp -

I certainly don't want to start an ruckus, but I have a 1976 Jeep CJ7 Renegade with 35,000 miles on it. It is completely stock and has the AMC 304 with T -18 behind it. We have owned it for 15 years and bought it from the original owners. It has never been modified since it left the factory. I have also owned a 1977 and 1978 CJ7 with a AMC 304 V-8 and the T-18 .


renegade.jpg


I also have an AMC Jeep sales brochure from 1976 that clearly demonstrates that you could order a CJ7 with the AMC 304 V-8 and the T-18 . They were not very common, but they are out there. I'll try to find it and scan the page in.

Colorado-

No offence taken. If you have the brochure please post a copy so we all can learn. My source for the answer to the question would be Moses Lundel’s book “The Jeep Owner’s Bible”. Unfortunately I have not unpacked all of my jeep books from a recent move so I can’t give you the page number but it clearly states that 1979 was the only year that a T-18 could be ordered from the factory behind the AMC 304 in a CJ. I had a discussion over the T-18 on another board with a guy from Billings, Montana a few years ago. He was so sure that the T-18 had never been available from the factory behind the AMC 304 that he offered to ship me his CJ T-18 for free if I could provide a creditable source to the contrary. After showing him the page from Moses’ book the existence of the combo was conceded however I’m still waiting for my CJ T-18 Transmission to arrive from Montana. Humm….

We all know the 1976 CJ was a bastard child of sorts as it used leftover parts from the last version of the CJ combined with the latest and we know Jeep used the close ratio T-18 until they ran out then switched to the wide ratio. Maybe this looming change over had something to do with the T-18 offering. Also I have never seen or heard of a factory T-18 behind the AMC 304 in a 1977 or 1978 CJ. As far as your 77 & 78 CJs I suspect they are swaps; remember that it is possible to put a T-18 behind either the I-6 or V-8 in those years using 100% OEM parts with no fuss or muss; just bolt it in.
 
Remember, if your the right dealer, and have a little pull you could order options from the factory that weren't necessarily advertised. Look at the offerings from Don Yanko with Chevrolet. Don could order about anycombination he wanted and Chevrolet would build it for him. I would almost bet from time to time AMC did the same thing for their dealers. If I were plowing snow (I have plowed snow with a Jeep) with a Jeep I'd want the power of a V8 and the strength of the T-18 .
 

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