Dauntless- Tranny Swap

So, I bought this cj with dauntless and t90c. I have an extra t14. What all do I need to get the t14 installed.
Thanks for any advice on the tranny swap.

 

Is this a cj-5 ? What year ?
Tranny swap should be pretty easy if little to nothing was modified from standard.
At a minimum you’ll need to swap the transmission insulaters.

 

I am doing the same swap except from a t86 to a t14. You will need a big hole transfer case (if your current case behind the t90 is an earlier small hole), crossmember, frame to transfer case mount, bell housing adapter meant for the t14/t86, skid plate for t14 and you might need a longer clutch cable too. Driveshaft you should be able to reuse.

 

You sure it's a T-90C?

Note that the T-14 and T-90 front patterns are different, so you can't blindly swap one for the other. Including the input shaft stickout, the T-90J is the same length as the T-86 or T-14, or very close. T-90A and T-90C are shorter.

The factory installation of the V6 with the T-86 or T-14 has a thick adapter that uses a long input shaft (1971 is different). I believe the overall length of the engine and adapter with the factory V6 is the same as when using the more common long T-90J input shaft and its T-90A adapter.

There is also a thin adapter that uses the original T-90A or T-90C input shaft, but this will have a shorter overall length than the factory setup. I believe that, using this adapter, you also have to move the transmission forward to clear the firewall.

Also realize that the T-14 from the '72-75 AMC-powered Jeeps is pretty common, and different/incompatible from the T-14 used with the V6. The T-14 was also used in Jeep pickups and Wagoneers with the six, which is either the same AMC version or an additional different incompatible version.

 

I performed the T-86-to-T-14 swap in my 67' Dauntless. T-14 mates right up with some minor issues. Here is some information from the Novak site which, I've found from experience, is accurate: "The earlier T14 had a 1-1/8" x 10 spline input shaft (or "clutch shaft") and its pilot tip is ~19/32" in diameter. Later AMC era T14's had the same spline configuration, but the pilot tip increased in size to ~3/4" in diameter." You can read all about it and other T-14 facts here: The Novak Guide to the Borg-Warner T14 Transmission

I purchased mine with the driveshafts and the correct transfer case attached. I could probably have used the original T-86 driveshafts, but I felt that I didn't need to create any other issues with the swap. The skid plate is the same. The transmission is slightly longer than the T-86, therefore, the clutch pedal bracket (bellcrank) will need to be located further back on the frame and you will need a longer actuator rod, which is available. Nothing to do from above, as the length differential is not enough to cause an issue with the shifter cover/shift boot. By the way, I love that transmission. Synchronized first gear is a big plus in my mind, but that's just me.

 

from what I remember of my t86 to t14 swap: I had to move everything back about 5/8" (cross-member/clutch linkage), lengthen front-drive driveshaft, and shorten the rear.
The hardest part was lining up the clutch as I had the trans/transfer/OD as one piece and was fighting the jack.

You might get lucky as did with the frame holes being drilled already.

 

If the OP actually has a T-90C, experience with the T-86 won't help. The T-90 front pattern is smaller than the T-86 or T-14. And the input shaft length is different. Not bolt-up compatible. I covered that above.

 

Thanks all for the info. The T14 is staying. Just going back to all stock.

 

Just out of curiosity, doesn't the T90C have a lower Ist gear ratio? 3.4:1ish? Is the T14 stronger behind the V6?

 

The T-90C does have a somewhat lower 1st gear. Novak has a page: The Novak Guide to the Borg-Warner T90 Transmission

The T-14 may be stronger than the T-90 - likely in the same league. I think the main motivation for the change by Jeep is the T-14 is a more modern design. The T-90 uses a sliding 1st-reverse gear, and is only synchromesh in 2nd and 3rd. The T-86 is functionally the same as the T-90. The T-14 uses a sliding collar for 1st and reverse instead of a sliding gear, which provides synchromesh in all forward gears.

The T-86 was something of an intermediate design, sharing the gear sizes and majority of design with the T-90 and the larger front pattern of the T-14. The first couple of years of the 225 Jeeps used the T-86, then Jeep went to the T-14. Some swap out the T-86 with the T-14 because replacements seem more available than the T-86. Replacement T-86 gears are not available. If you have a broken T-86, barring finding now-unobtainable replacement gears - you can repair by emptying the case and installing all-new T-90J gears. No mixing gears allowed - the gear design is different and only the interior dimensions of the T-86 case match the T-90.

 

Guys, I am thoroughly unimpressed with the longevity of the T14. I have found it to be a weak link behind the V6. I've seen a number of them broken over the years (I managed to loose two). Parts are unatobium as well.

If I were going to go through the hassle of a transmission swap, I think I would opt for a more robust option. On a personal level, I swapped in a T18. I found the overall length to be within 3/4" of the stock T14 + adapter. Other options would a a SM series or even a NP. If you want to keep a three speed, I'm sure the T150 could be adapted as well.

Just a personal opinion based on my experience.

 

I think you mean T-15, not T-150. These are different transmissions. We had a thread recently about this topic ... T15 / T150 Compatibility (or T15 Top Cover Wanted)

The T-150 is a Ford passenger car 3-speed, built on license for Jeep by Tremec. Standard transmission in CJs 1976-79 for both sixes and V8s. Contrary to its Novak page, it is not a Borg-Warner transmission. It has a seal between the transmission and transfer case, which the Borg-Warner 3-speeds do not. This seal requires a shoulder on the output gear, and that only exists for the Dana 20, not the Dana 18. Aside from having a Ford front pattern that is different from the T-86 and T-14. It is reputed to be stronger than the T-14, but not as strong as the T-15.

The T-15 is stronger than a T-14. It is a Borg-Warner 3-speed, and has the same front pattern as the T-86 and T-14. It has a six-spline output, same as the T-90 and Jeep T-18s. It does not exist with an input gear length that works with the 225 without some adapting. Novak has an adapter Adapting the Chevrolet & GM Standard Shift Bellhousings to the Jeep CJ & FSJ Borg-Warner T14, T15 & T18 Transmissions that's comparatively inexpensive. Ken (oldtime) posted a thread on making an adapter - you can follow his work if you want to make your own adapter.

Unfortunately T-15s also have some parts availability issues. BTDT. Not to the degree of the T-86 I presume, but I would lay in a parts unit or two if I regularly abused my T-15.