T-18 / T-90 Swap (L-134)

I have been contemplating the same swap.  I have collected a T-18 from 65 F100 with the 6.32 first.  I'll be watching.  I have batted around the idea of a custom bell housing to deal with the 1/2 inch shorter input.

Falcon !   _ _ _ finally some new interest in the T-18 transmission. Yeay

I too have gathered.

I like the Clocking of the IH-Scout T-18 / t-case being lower than the T-90 / D-18 setup.
I looked at Scout T-18 the other day, and the bottom of the transfer-case is about flush with the bottom of the T-18. The Reason I like this is because of the additional length of +- 3.5-inches the angle of the U-joints gets sharper and if the clocking (drop) of the T-case Output is lower, then that decreases the U-joint angles.    _ _ _ a Good-thing for Willys.

My thoughts so far:   my head is swirling, because everytime I get an idea, I toss it upon review. A first thought was to make an adapter plate, but then the Ford input may be too short if trying to mate to the L134 bellhousing with an adapter plate similar to the one's that were once offered with the F134.
   I haven't spent enough time looking at input shaft options and such.
But, I see you have found a clutch disk that might just work.

Do you know the length of the input shaft that was an original option with the T-98 with the F134 ?

I know of a gear-maker in Portland, Oregon, who can probably shorten a wagon or pickup shaft to your spec.

Another thought, and I am just tossing ideas:
turn the I.D. of the L134 bellhousing index hole to match the input bearing retainer you choose.
   Then, with the transmission up against the bellhousing, fire-up the welder, and with nickel rod weld mounting ears onto the L134 bellhousing to bolt the transmission directly to, alleviating an adapter plate.
   Then, you have the gear-maker modify your FSJ (full sized jeep) input shaft to the length you need, and he can probably extend the splines further onto the shaft as needed. Don't know about heat-treatment and such, but he would have the source for that.
    Just ideas, and I have not got down to looking at options either.
It makes my head hurt. :)

   I HAVE searched the net for the Rare optional input shaft that allowed the T-98 to mate to the F134 engine/bellhousing, and have not yet found one .


   One last thing, the T-18 is a real Booger to disassemble.
   A NP-435 will literally fall apart in your lap. Very user friendly.

   Len
   

Edited by Greaser007 - 24 Feb. 2019 at 2:33am

Sure! Late 70’s early 80’s 2.3 mustang. Just make sure it’s the 10-spline. It’s 8.5” disc. It will fit the ford 1-1/16” shaft. 

Your friend did a very nice job!    

Lee

I am going from memory but questioned if the input shaft from a FSJ T18 would work in the Ford T18.

 

Ive been working on the swap little by little when im not working on the roll cage. Im going to do some test fitting with the ford shaft to see if I can make it work. I also started working on a backup plan. I turned the FSJ shaft I had down to match the sickout length of the t90. did the lathe work but now its in the mail on its way to moser to get the splines cut. 

I finished machining the bushing... it still needs drilled but is 95% done. 

Thanks! I think I better make sure this one actually works before I recommend it to anyone else. The whole time I’m working on this I can’t help but wonder why AA or Novak doesn’t make this conversion??? With the rarity of finding a t98 and how common the t18 is....seems like a no brained. I bet they would sell a bunch of them. If this works and anyone else wants to give it a try I will help you in any way I can.

   Falcon:

    Today I was doing some measuring on my L134 Bellhousing, and the mounting holes on a T98 trans from an early Ford, '64 maybe, not sure, but supposedly an F-250 with divorced t-case. The mounting holes up top are about 8-1/2" apart.
That gives me room to weld mounting ears onto the L134 bellhousing. I didn't check width of trans body to see if there is clutch cable interference.
   But, just as you have done with your input shaft, that has to be the ticket.
Or one ticket of the 103 ways to skin-the-cat.   right !   hahahaha

   Very nice work on that input. Now, I am going to have to call the gear maker in Portland to see if he would be interested in cutting one down for me.
   From what I remember _ _ _ and it is Foggy _ _ from when I did gobs of research way back in 1984 when I put a T-18 in my CJ-7, was that the output shafts are the same between the T-98 / T-18.   Correct me Oldtimer if I am wrong here, but I just have that rosy feeling, because I have one that I have packed around with me since purchasing a garage-full of jeep stuff in 1988.
As oldtimer mentioned, there could be differences in the needle bearings from input-to-mainshaft. This I am not familiar with currently.
   My investigation revealed a pilot hole O.D. on the Scout T-18 bearing retainer of approx. 5-inches, whereas the old Ford T-98 had a bellhousing pilot of closer to 5-1/2-inches so yes there are variances.
    I centered tape on my L134 bellhousing to see if I had room for welding on transmission mounting ears, and turn the inside of the L134 to about 4-7/8-inch or thereabouts. (which would mean turning down the O.D. of the brg retainer to the 4-7/8 minud .002-inch. I would have to weld a piece of bar stock across the top of the bellhousing to reinforce where the pilot hole is cut near to the top as a stiffener and no-more.   Then I can leave the bellhousing in place an remove the transmission separate from the bellhousing.
    That other guy's pilot / retainer is very clever.

I have a question that I am not understanding here. Why is the O.D. of the new aluminum bearing retainer greater than the T-90 retainer ?
Are you opening up the diameter of the hole in the L134 bellhousing to accept the diameter of the Aluminum adapter ?   thanks

Thanks for all the wonderful photos, and there are probably more than a few of us drooling to make this swap.

   Keep up this great thread !   I know I am liking it.

So, today, I wound up wiring-in a 220V outlet for my 225 mig welder, and an outlet for my 220v air compressor. For the last 7-years I have been living off of extension cords from an RV stanchion. A real PIA, but I have made too many moves over the years, and now working out of a barn-conversion-to-shop.
   Hahahaha _ _ _ good ol "rural America" ways.

   But, I was wanting to make a template of the front of my old-ford T-98 transmission to lay it over the L134 bellhousing to see how "ear" placement lands. The front of the Scout T-18 transmission I have actually does not have ears to bolt it to a bellhousing, but has 4-studs that must attach the scout bellhousing to the transmission together.   Hmm, interesting.
   after doing some measuring today, I reached maximum brain-pressure, and jumped onto the electrical shop wiring. No conclusions yet.

    Len