Tea 18 time.

[Collin the Hen]

My T5 is toast.

I found a rebuilt T18/D20 assumed to be from a late 70's Jeep with a "V8 bellhousing" for a decent price. I only spoke to the seller, so I haven't looked at the transmission yet. Another is available, too.

Some questions:
Can a T5 bellhousing be modified to fit a Jeep T18?
Would the V8 bellhousing (assuming it came off an AMC V8 ) mate to my 258? Novak-Adapt says they interchange nicely. Compared to a shadetree mechanic and Novak machinists, "nicely" means a couple different things. :lol:
Clutch, T/O bearing, driveshaft lengths...

Yes, I have googled this, but as with most swap junk, I only found contradicting information and fad answers.

Any help would be much appreciated!

 

[Saddle Tramp]

The first question is did the transmission & xcase come out of a CJ and what year is it? If not out of a CJ then it would have come from a FSJ and you have a front input shaft problem, it will be too long as the FSJ used about an 8" adaptor between the front of the transmission and the bell housing. (The CJ T18 front shaft is about 7-1/2”) The FSJ transmission is still usable but you will need to change out the front shaft for starters. The other good news is the T18/D20 combo will have the longer shift rail shafts needed to move the xcase shifter forward so you don’t have to cut a new hold in the floor for the lever.

Assuming you have a CJ T18, I don’t know off hand if the center hole in the T5 bell housing will fit the T18. If it does, you will still need to drill & tap for the T18 bolts however the upper driver side bolt fits inside the bell housing with the nut on the outside and you need to notch the clutch fork for the bolt head clearance, shave the bolt head for clearance, and weld a nub on the side of the bolt to jamb into the bell housing to keep the bolt from turning when you tighten the nut. See the web page below for more info on this.

The year of the transmission is important to know what the granny low gear ratio is. 1972 to 1976 are 4:02 and 1977 to 1979 are 6.32. (I’m referring to CJ T18s here, not sure on FSJ) Of course the 6.32 ratio transmissions are the most coveted due to the lower ratio.

An AMC V8 bell housing bolt pattern and an AMC I6 bolt pattern are one and the same so if you can get the donor bell housing (again assumes it is from a CJ) you will be able to bolt right up. This should take care of the bell housing/T18 blot pattern issue too. Make sure you get the bell housing/T18 bolts if you can as it will have the special bolt I described before for the drivers side top. (The special bolt is no longer in production to my knowledge.) The clutch system is also the same so no change there.

I am not sure without looking it up as to the total length of the T18/D20 in relationship to your T5/D300. Check the dimensions on AA or Novak and add them up. On a 1977 to 1979 CJ the skid plate moves back one set of bolts as the T18 is about 3” longer than the T150 it replaces but again, in you case, 1984, not sure. This would affect your driveline length too.

Take a look at this site; it has a wealth of T18 swap info:

http://www.jeeptech.com/convtrans/cjt18/

 

[Collin the Hen]

Thanks for the info! I'll call him and try to weasel some more information from him. He doesn't know Jeep stuff well. I doubt he can even tell me from what year the transmissions came; they were "parts" that came with his Jeep.