how to tell the difference between a t-18 and a t-18a

[scotty]

Originally posted by Grantshire:
Weren't the T-18B's all the long shaft FSJ T18's?

nope.as mentioned in my 1st post above,a friend is running a 6 cyl t18 in his cj,wich is the "medium" shaft,with a short 1" spacer between the tranny and bell. it is cast t18 1b.

if by "long shaft" you mean a tranny with any spacer between the bell and tranny, i guess that is possible. it may be that "t18 1b" is the designation for any t18 used in a FSJ,as i have not ever really checked any t18s from scouts,fords,or cjs...

[Knucklehead]

Hey Gwamp, what is this combo out of? I'm still interested.

Jon

[Grantshire]

I am by no means an expert on this subject. However, in preparation for my TH400/QT to T-18/Dana 20 swap I have been doing a lot of "investigating". Along the way I have picked up two T-18's. One is a long input shaft T-18B (6.32 1st gear) that came from a mid 70's V8 FSJ. Becasue it was behind a V8 the spacer between the transmission and bellhousing is over 4". The other T-18 (don't know if it is a "B" or not yet - just got it, but it has the 6.32 1st gear) is in the 79 J10 donor truck I just bought and is attached to a 258 6 cylinder. Because the 6 cylinder is a longer engine than the V8 the spacer between the transmission and bellhousing is only about 3/4" thick. The two bellhousings appear to be identical so my bet is so are the front T-18 shafts. The J10 was originally an automatic (based on the steering column) so I don't know its T-18's vintage. Bellhousings from earlier FSJ's were very deep and, therefore, did not have the 4+" or 3/4" spacers.

I also have a 74 Scout II with a T-18/Dana 20 combo. However, it has the close ratio gears (4.?? 1st gear). I have not climbed under it to see what markings are on it but I know it has a much shorter input shaft than my other T-18's. All of the Ford T-18's are also shorter than the FSJ T-18's.

[Gwamp]

Originally posted by 66HD:
Hey Gwamp, what is this combo out of? I'm still interested.

Jon

It came out of a 74 J-20. I haven't had a chance to check to ratio. The combo is still in the wheelbarrow in my basement. Do you have a Forward air near by? That is about the only reasonable way to get this to you.

[Knucklehead]

I'll check and see.

So what will I need to get this on the back of a 360. Does this setup have the extension on the front of the tranny and the long input shaft?

thanks

Jon

[Knucklehead]

Gwamp, It looks like there a hub in denver. Let me know

thanks

[Knucklehead]

Gwamp,

You got email

[scotty]

Originally posted by Grantshire:
The two bellhousings appear to be identical so my bet is so are the front T-18 shafts.

front t18 shafts?im alittle confused by what you mean there... if youre refering to front drivesahfts,i bet you are right. the spacers are there to make the tranny and t case shifters come thru the same spot in the floor,despite the differences in engine mounting,so the transfer case should be in the same spot,and use the same driveshafts

ill bet,however, when you get the t18 out from behind the 258,youll find that it is also cast t18 1b,and is also the wide ratio. this is the version my friend is running in his cj. [img]smile.gif[/img]

the scout t18 has a very deep bell,and around a 9" input shaft,IIRC,so it is about the same length as the 6 cyl t18 with the short spacer.

the ford t18 has a short shaft,like the cj t18(round 6") which is why it is popular to swap into a cj. the t150 bell bolts to it and is the right depth,so the cj guys just need to adapt a d300 or d20 to the other end. a ford or cj version t18 with a d20 is about the shortest granny truck 4 spd you can get,other than the sm420.

for whatever any of that info is worth anyway [img]tongue.gif[/img] id defintely be interested to know the casting # of some ford or scout t18s,be they wide or close ratio...

['71j2500]

my t-18 is marked t-18-b1 and has the 6.32 ratio first gear

[Bryan]

Ok, tax return time is coming up and I plan on spending some $$ on the J10, one of the first things I want to do is get a t18. I have a t15 now behind a 258 I6. Do I need a t18 from behind a 258 or can I use one from a v8 and use the t15 bellhousing/spacer since I think thats the only difference???? Thanks...

[Grantshire]

Scotty, I was refering to that sticky outty thing on the front of the transmission (input shaft). Overall length of the input shafts on T18's range from 10" to 16 3/4" (Advanced Adapters lists 9 different lengths between 10" & 16 3/4"). "Stick out" is about 2 5/8" less than overall length. The T-18B I have in the garage has the 16 3/4" input shaft. My guess is that the one in the J10 behind the 258 is also one of the long ones. Both appear to be the wide ratio 6.32 1st gear T-18. The Scout T-18 I believe has a 12 7/8" overall input shaft length and is close ratio (4:1 1st gear). I also believe there is a difference in shaft diameter between the Jeep/Ford T-18's (1 1/16" dia.) and Scout T-18 (1 1/4" dia.). Splines are different too. Some Scouts also came with a T19, where all gears are syncronized (first gear isn't on a T-18).

You are correct that the adapter thickness difference between the V8 and 6 cylinders is to keep the shifter in the same position regardless of engine type.

[Knucklehead]

Gwamp,

I sent you another email.

Jon

[scotty]

Originally posted by Bryan:
Ok, tax return time is coming up and I plan on spending some $$ on the J10, one of the first things I want to do is get a t18. I have a t15 now behind a 258 I6. Do I need a t18 from behind a 258 or can I use one from a v8 and use the t15 bellhousing/spacer since I think thats the only difference???? Thanks...

you can use the v8 t18 behind a 6 cyl,however: it will push the tranny and transfer case shifters about 5" rearward,wich may or may not give some interferance prollems with the transfer case shifter and the front seat.

i am running a v8 t18 out of a 77 j20 behind the 258 in my GW. i actually like the position of the shifter where it is now,its ergonomically very nice [img]smile.gif[/img] im running a scout d20 behind it with home made twin sticks,and im running plastic racing jeats from summit,so i dont have any clearance prollems there. i do remember when i was running a spicer 18 with factory seats that i had to bend the levers for seat clearance,but that is prolly apples to oranges in comparison to the jeep d20 with the pole shifter.

the other prollem that arrises is that it pushes the tranny crossmember past the rearmost set of holes,and partially past the boxed section of front frame. my stock mount was toast,and i could find another,sp i just located the crossmember with one of rearmost holes,and drilled the other 2 thru the frame. i didnt bother to install a bolt in the top corner that isnt on the boxed section.

obviously this is going to affect the driveshafts as well,so you wont be able to use them from the donor rig. youll be able to shorten the rear shaft to work,but youll need to have the front retubed,or find another one thats too long so you can cut it down.

i just bought all my clutch stuff for a 77 j20 with a 360. the pilot bushing i believe i bought for the 360 as well,and it fit the 258 crank. it has been awhile,so i guess i could be wrong on that-might wanna compare a pilot bushing from a v8 to a 6 before purshasing

grantshire,i gotcha on the stickout length thing-it for soem reason confused me cause of how it was phrased on the 1st post [img]redface.gif[/img]

[Bryan]

Thanks Scotty, for the info. Sounds like it might just be easier to find a 6cyl t18. I guess the question still remains though, is it the input shaft and spacer that is different between the 6cyl and v8 t18's, or is there more to it than that. I dont want to have to start drilling holes in the frame and floor if I can avoid it.

[scotty]

yes,that is the only difference. but swapping to a shorter,6 cyl input shaft requires you to a)find the shorter sahft,and b) completely disassemble the tranny to swap it. not out of the range of a DIYer,but there are lots of gears and snap rings,not to mention needle bearings that must be held in place during reassembly with heavy grease or vaseline

for whatever its worth,the new hole for the shifter will be in the tranny cover,wich is a replaceable part if you ever wanted to go back to an auto. the t case sifter im not so sure of-dont remember if a pole-type stock shifter sticks thru the tranny cover or floor itself. my floor has several different holes,now coverd with sheetmetal,from various tranny/x cases in the past

there is not really a way of using the stock crossmember without drilling some holes. only other option would be maybe to design somthing custom

my truck is a trail only rig with no carpet or interior to speak of,and the fabbing doesnt bother me,so for me the v8 tranny worked out pretty well.

youre right tho,if you want a bolt in swap with minimal cutting/welding/drilling finding a 6 cyl version is the way to go