T-14 to T-15 or T-18

If I have a stock 74 with a t-14 and 258 is the t-15 a direct bolt in replacement? How about a t-18?

 

The CJ T-18 is a direct bolt in if it comes with the T-18 bell housing.

 

So I guess I should have asked:

Is the stock t14 bell the same as the t15 and t18? Or do I need to get a new bellhousing?

 

I got some indication in the past that the T-15 will bolt up to the T-14 bell, but I don't know for sure. This came up in reference to using a T-15 in a V6 CJ, where the T-14 bell is the only one available.

However, Intermediates are easy this way. If you have the AMC T-15 bell, that will bolt up to the 258 - 304, 360, 401, 232, 242, 258 all the same pattern, so no worries. If you find a T-15, it should be fairly cheap but get the bell. The T-14 1st is slightly lower (3.1 v. 3.0, 3%) but the T-15 2nd is a more useful passing gear (2.61 v. 1.83) and of course it's stronger.

As Chuck wrote, the T-18 from a CJ will bolt in if you have the bell that goes with it. The '72-76 close-ratio T-18s uses a plate adapter and the T-15 bell (IIRC), so you need those too, and that transmission doesn't share gears with the more common wide ratio transmission. The 77-79 wide ratio T-18 from a CJ should bolt in too - don't know the specifics but I'd expect it to be hard to source.

hth!

 

Thanks guys. This info was for a friend actually and not me. He has blown 2nd gear out of 2 t-14's in less then a year and I think he is getting a little aggravated.

 

If interested I have a bellhousing and clutch fork available for the T-15, cheap. The T-15 tranny is already gone though.

 

Great I will let him know. Thanks.

 

How do the TJ transfer cases match to the T-15? I've got an NP231 coming out of a '99 this week.

 

No easy match AFAIK. In 1979, Jeep went to the New Process (NP) circular pattern on all their vehicles. Prior to that, all the manuals used the D20 Texas pattern and the TH400 used the unique BW1339 adapter. There's no easy way to cross that boundary.

 

I looked in the parts book and it appears that in the intermediate years the T14 and T15 use the same bell housing(part # 321 5152). Also in the intermediate years for the T18 they used an adapter plate (part # 992 667) between the BH and transmission. Unless you have the whole setup from a donor Jeep(scarce) I would go with the 76 and later bell housing and Ford length input shaft as the whole setup would be more than a couple inches shorter so you can have your rear driveshaft as long as possible. The intermediate bell housing is better then an inch longer than the later one, plus the adapter plate between BH and Tranny would add another inch in overall length. Also the T18 is a couple inches longer then the T14/T15, so the whole setup would make the rear DS quite short. There is quite a bit of info on this swap on this forum and in my opinion well worth doing for trail. If you just have a road driver with little trail use the 3 spd should be fine.