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T86 to T15 conversion

T86 to T15 conversion

mriplaybass

Full Time Jeeper
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Location
Wisconsin
Vehicle(s)
1979 CJ7 304 T18 w/6.32 lo d20 w/3.15 TeraLo D44 rear & D30 Front w/4.56 Eaton Elockers front and rear,
1959 CJ5,
1954 CJ3B,
1967 CJ5,
1947 IHC KB1,
1947 IHC KB2,
1947 IHC KS5,
1967 Mustang Coupe,
I can't find a T-86 to replace the one that was sold to me with my 59 CJ5 with a cracked case, so I am considering converting to a T-15 . Does anyone have experience with this conversion? I know that both the T-86 and the T-15 have the same face bolt patterns and they both have a 1 1/8" by 10 spline input shaft, but there is where my knowledge ends. :confused: Is the input shaft the same length? Is the pilot bearing the same size? I know that the T-15 is slightly longer, but I have not ordered my drive shafts yet, so that is not a problem. Any info would be greatly appreciated!
 
I would be glad to relate what I did to install a T-14 in my '67 CJ5 replacing the T-86 . So the question is T-15 or T-14 . Two different animals.T-14 also used behind Dauntless Buick 225 V6 V6 and Rambler inline six (I-6).
:) mike
 
I just built a 1957 CJ5 with a 327. I got an adapter from Novak. I used a model 20 Transfer Case with the model 18 gears. I also installed a Warn Overdrive . It all worked out fine, except the Transfer Case overfills with gear oil from the Transmission . You should install a sealed rear bearing on the Transmission . I also plan to plug the small holes in the back of the Transmission to make sure none on the Transmission oil gets into the Transfer Case .

When Jeep starting installing the T-86 Transmission with the 225 engine, the Transmission broke a lot. We solved the problem by replacing all the gears with T-90 parts. It worked out great.

Jeep dealer from 1963 to 1982
 
Yes the T-15 should bolt in and is stronger than the T-14 . It is also some fraction of an inch longer, enough that driveshafts will likely need modified and I believe it uses a 10 spline output so you should get the Transfer Case main drive gear with the Transmission . The T-86 , T-14 , and T-15 all share the same bolt pattern.
 
Thanks for all your help. :)

mriplaybass and I are building a CJ5 and he has been my much better half since 1988. He forgot to mention there was a Dana 20 behind this T-86 and our axles are Dana 30 and Dana 44 from a 74 CJ5 . I'll try and get his profile info updated.

Our build thread: http://www.jeep-cj.com/forums/f98/1959-cj5-one-piece-time-21347/ And I need to update it...:o

We actually found a T-15 /Dana 20 just a few miles from our home last night and bought it on the spot...:D The gears look good and the Transfer Case shifts much better (less slop) than the one we have. Of course the adapter plate we just got to replace the cracked one is the "wrong" one now, but Advance Adapters has the one we need complete with pilot bearing...and it costs more than the little package we picked up last night...:rolleyes:

We still have not ordered driveshafts as we have been waiting to figure out what Transmission /xfercase adapter combo to figure lengths as these will probably be custom length...:rolleyes:

Yes - we are still going to CO!

mstar - Mike - You have already built some of the things we are building now - I can tell by the pics you have posted in other threads. You will probably be hearing from one of us - thanks for your offer of help!..:notworthy:
 
We still have not ordered driveshafts as we have been waiting to figure out what Transmission /xfercase adapter combo to figure lengths as these will probably be custom length...:rolleyes:
If you are using the Dana 20 with its high output and getting custom driveshafts made, it is absolutely worth the extra expense of including a double cardan joint.
 
Oh, and don't throw the T-86 . A lot of people looking for those pieces and the rear bearing retainer is the one used with a lot of Transmission /Transfer Case adapters. Definitely worth a classified post here and at Early CJ5 .
 
Duffer, thank you for pointing out the option of the T-15 behind the V6 .To be honest I did not know they where that much alike. Sounds like a great upgrade over the T-90 ,86,14 . with out the expense of a 4 speed.
I will be keeping a look out for T-15 's if one comes up for reasonable price.
One ? if you are using the T-15 with a dana 18 will I just use the output gear that goes with the Transfer Case . I have the 29 tooth gear from the T-86 .I guess that will go onto the T-15 mainshaft? Thanks, mike:)
 
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Oh, and don't throw the T-86 . A lot of people looking for those pieces and the rear bearing retainer is the one used with a lot of Transmission /Transfer Case adapters. Definitely worth a classified post here and at Early CJ5 .

If you are using the Dana 20 with its high output and getting custom driveshafts made, it is absolutely worth the extra expense of including a double cardan joint.

Thanks duffer - All good advice!

We have been looking into the double cardan rear driveshaft. I have only looked at the Tom Wood's site and if there are others to check out please let us know.

Right now the pinion angle is about 8 degrees and with the Buick 231 V6 as our engine we may not need the double cardan joint - BUT I have not measured the length yet which may be the deciding factor....AND I can see the wheels turning in my husband's mind and he might want to put a bigger engine in some day..:eek:..he is the gear head - I am the CJ lover..:D

Regarding the T-86 - we have a 67 CJ5 stock that we hope to restore someday so this will probably go in the "sit and wait for that build" pile of parts. I think we already ordered a seal kit too....oh well - the joy of owning multiple CJ projects. We are also members on ECJ5 - same usernames - but I have the build thread on this forum.

Thanks again.
 
Duffer, thank you for pointing out the option of the T-15 behind the V6 .To be honest I did not know they where that much alike. Sounds like a great upgrade over the T-90 ,86,14 . with out the expense of a 4 speed.
I will be keeping a look out for T-15 's if one comes up for reasonable price.
One ? if you are using the T-15 with a dana 18 will I just use the output gear that goes with the Transfer Case . I have the 29 tooth gear from the T-86 .I guess that will go onto the T-15 mainshaft? Thanks, mike:)

My bad. It's the T-14 that is odd man out 10 spline output. The T-15 uses a 6 spline output which is the same as the T-90 /T-86 and therefore your old 29 tooth main gear for the Transfer Case will work.

The main impetus for installing a 4 speed is usually for the deeper first gear but that almost always comes with a lot more strength along with a lot more weight/height. Whether or not that swap is desirable will be largely dependent on your use, gears, and tires. As with most things, there is more than one way to put the kitty out of its misery.
 
:) I hear ya on that. I don't have any plans for a change myself but I will put the info in the memory bank. thanks,mike
 

Thanks JR!

After much scraping of grease and gunk it became a question to us as to what Transmission we actually bought (regardless of what the guy told us - I doubt he even knew...). There were only 6 bolts on the shift cover plate, and the T-15 was supposed to have 8. After more scraping on the sides the 13-02-065-906 W G DIV confirmed we now have a T-14 . This was supposed to have come out of a '75 CJ5 , but who knows where it came from. It does seem as thought the T-14 and Dana 20 were a matched set. It still seems to be in reasonable shape. There is a little pitting on the gears on one side where it must have sat for a long time without turning. We hand sanded these surfaces to make the meshing sides as smooth as possible. The fluids looked good when we split the tranny and Transfer Case .

We talked with both Novak and Advance Adapters. While the folks at both places were very nice, the Novak rep told us the T-14 's were pretty much only good for parting out and tried to set us up with a very nice Muncie Transmission for only about 2K. He said he would sell us an adapter for our T-14 , but we would just be wasting our money as the Transmission was going to fail pretty soon and there are no parts made for it.

After some discussion that maybe this project was not meant to be, we decided to call Advance adapters. We ended up ordering an adapter kit from them. We will just have to be gentle with our doomed fated Transmission and be on the lookout for a replacement when it fails.

Thanks for the help/info though..:)
 
Well, it's all relative. The T-14 is relatively a MUCH BETTER Transmission than the T-86 and with a V6 and somewhat restrained tire size, it should give you decent service. And I don't think parts for it are as hard to find as T-86 parts.
 
T-14 is still a good tranny for you.

I believe there were versions of it that came stock with the Dauntless Buick 225 V6 , but you may have the later model with the larger tip.

The Borg-Warner T14 Jeep Transmission - Novak Conversions

You may be able to just get away with a new input shaft and the correct bell housing.

I may be totally wrong, I'm just getting back from camping and rushing checking a few posts before starting work...

:chug:
 
T-14 is still a good tranny for you.

I believe there were versions of it that came stock with the Dauntless Buick 225 V6 , but you may have the later model with the larger tip.

The Borg-Warner T14 Jeep Transmission - Novak Conversions

You may be able to just get away with a new input shaft and the correct bell housing.

I may be totally wrong, I'm just getting back from camping and rushing checking a few posts before starting work...

:chug:

:)

JR, Did you bring that Jeep back in one piece this time? (LOL)

:D:D:D:D
 
haha :laugh:

I didn't take it. Havent had the chance to fix it yet from last trip to local OHV park (Spun axle housing still).

Wife keeps planning :dung: for the weekends! Doesn't she know thats my jeep time yet???

:chug:
 

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