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Discussion Starter · #1 ·
I know this has been hashed out before. I'm using a Buick 225 in my 67 Jeepster. I want to keep a manual transmission but go to one with a granny gear. I am looking into the SM420. or Ford 2wd T18. What I really don't want to do is pay 500 bucks each for the adaptors. I would rather use a combination of parts that might be able to be replaced out of a Salvage yard. I believe the Ford T18 can be bolted to the stock V6 Bell housing with some work to the Bell housing. What about the input shaft and clutch ? Since the Jeep Dana 20 won't bolt up to the ford or the Sm420 then what about changing to a different xfer case ? IE ford or Toyota or GM. Adaptor plates that can be made locally are ok and some machine work to modify parts is ok. I just don't justify the one of a kind adaptors expense. I'm starting with a buick 225, 3 speed stick (T14A ?) Stock Dana 20 and stock rear end. DanA 30 with disc in front. I know that the driveshafts are going to have to be custom but that's a given as heavier duty than stock is needed and there is usually a driveline shop close around. If I'm wrong on any of my thoughts let me know because I've just started researching this out. Thanks in advance for any help.

Lenny in Colorado Springs
67 Jeepster 225 V6 & 3 speed
96 Dodge Ram 2500 V10 AT CC LB 4x4
 
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Discussion Starter · #2 ·
You need to modify the front of the tranny to fit the bellhousing. For an adapter find a Scout T-18 with the
20 adapter and output shaft. You can put the output shaft and adapter in the ford case. You have to redrill
the case and plug one hole for the adapter to fit. If you don't plug the hole (bottom left corner on the back)
you will have a massive oil leak. The other thing you can do is try and find one of the old Pontiac
Bellhousings that have gm and ford tranny bolt patterns on it. If you can't find an adapter then e-mail
me and I might be able to locate one. Good luck. Nickmil.

 

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I can kinda answer your question. Here is what I did to my Ford T-18. I found a Jeep version T-18, with the 6.32 granny low 1st gear, in a junk yard that still had the Dana 20 and adapter plate bolted to it. If I remember right, the donor Jeep vehicle was a mid-late 70's Cherokee. I also had found a 2WD Ford T-18 a few months eariler in the same junk yard. Total cost for both transmissions trasfer case with adapter and shifters, was just under $300. I'm sure that prices vary form place to place.

I then had both transmission torn down. I used the Jeep T-18 mainshaft into the Ford T-18 transmission. I then indexed the Jeep T-18 to Dana 20 adapter plate onto the Ford T-18 transmission case. I then drilled and tapped the Jeep T-18 to Dana 20 adapter plate bolt pattern into the Ford T-18 transmission case. I used some 1/2" deep set screws to plug the no longer needed Ford T-18 2WD tail housing bolt holes.

My Ford/Jeep T-18 was for a Small Block Chevy. I purchased a bellhousing from Lakewood Industries that allowed the Ford T-18/Small Block Chevy combination as a direct bolt on. Ford and Small Block Chevy transmissions have input shafts that are 6.5" long. Most Jeep transmissions have input shafts that are longer than 6.5". Most Jeep transmission have bellhousing adapters between the transmission and bellhousing.

I can not comment on the 225 bellhousing question. I can say that the Ford T-18 input bearing housing could be turned down in diameter on a lathe to fit a smaller bellhousing center hole. I would think if the 225 bellhousing depth is for transmissions with 6.5" input shaft length then maybe getting the Ford T-18 input bearing holder machined to fit the 225 bellhousing center hole, then you could drill and tap the Ford T-18 bolt pattern into the 225 bellhousing.
dave

 
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Discussion Starter · #4 ·
I took a slightly different aproach....

I grabbed a jeep T-18 from a late model cherokee, and a T-18 from a two wheel drive ford (F250?). I swapped the ford input shaft into the jeep case. That way I didn't have to mess around with the Dana 20 adapter. On the bell housing side I got a chevy SB to ford bell housing from Parts Mike in california. He drilled the two lower jeep case holes into the back of the bell housing. I used a chevy 10.5 in pressure plate and a jeep clutch disk (ford and jeep have the same splines on the input shaft.) I did have to turn the outside diameter of the input bearing retainer down to the size of a chevy throwout bearing. That was a ten minute job on the lathe. The only machine work was the bearing retainer.
Total Cost:
2 transmissions $130 ($65 each)
New bellhousing $400
Machine work $20
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Total $550

Compare that to the cost of a SM420 to Dana 20 adapter (~$500 and you still need a tranny) and you realize this is the cheapest route.

Just my $0.02

My name is Ted, and I'm a Jeep-a-holic. /wwwthreads_images/icons/laugh.gif
[email][email protected][/email]
 
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