73 Cj5, 360 V8, Possible Transmission Swap

Hey friends, I have a couple of questions regarding the transmission in my CJ5. As noted, it currently has a 360 with a T15 trans. I have the jeep completely taken apart down to a rolling chassis. I am rebuilding/repairing anything that needs it, as I go along. Currently I am at the transmission. My first dilemma is the shift lever has been hacked off for some reason, it's only about 13 inches long. BostonBob is searching his parts for a replacement one now. After I got the shift lever situation figured out, I had planned on taking it on to a transmission shop for an inspection and rebuild if it's needed. I pulled the top cover and it looks okay to me but I have zero experience with manual transmissions and for all I know it will explode the first time I hit the clutch. This jeep has never been running for me, other than a very quick roll back and forth in the driveway when I realized the brakes had taken a vacation. My question is, would it be worth keeping the T15 and going through the parts hunt and possible repairs costs?, or change to a different model that is more common and available. I see that Novak has fully rebuilt units, that can be adapted over to my 360 and Dana 20. I wanted to keep the jeep mostly original, but with the 360, that kind of goes out the window anyway. My main use for the jeep is going to be a weekender, no serious off-roading really, but a low first gear would always be an option. Thought son this ?.

 

Mmm. "Looks good" means no broken teeth, no rust pitting, clean oil?

If it were me, I would remove and inspect the front main bearing for smooth operation, install new blocking rings, put it in and run it. R&R of these 3-speeds is pretty easy in a Jeep, and you won't be able to assess it much more than above by inspection. You won't be far behind if you run it and discover a problem.

 

You understand that the T-15 is the strongest 3-speed made? A different 3-speed would be even less appropriate for the 360. Any upgrade would be to something like a truck 4-speed, and would involve considerable effort and expense. There is nothing else that just bolts in. IMO the rebuild of the new transmission is the easy part of the swap, so you'd be paying Novak a lot for doing the bit you are likely most capable of. Plus the truck 4-speeds are so beefy that they usually require little attention. Suggest you read up about transmission swaps before you make any decisions. Where are you on the spectrum of capabilities?

The 360 is the same as the 304 aside from displacement. Larger bore, better heads with larger valves. Different balance, so you need a 360 flywheel and damper. Many owners sub the 360 because it's more available than the 304, and it's your best bang-for-the-buck if you want a performance upgrade.

 

For the stated use, I can't think of any reason you would want to swap the T15 out. And the 360 should have plenty of low end torque if someone didn't get carried away with the camshaft. Something that mitigates some of the need for low gearing. The only thing I didn't much care for with that engine was its abysmal mileage (no matter what induction I tried) and the non adjustable rockers.

I suspect you could pilot that as is over the Rubicon with minimal problems. If you need more capability off road, a locker (or lockers) would be much higher on my desirability list than a tranny swap.

 

Hey thanks for the advice. I did some research as suggested and the rebuild looks like something I could definitely do. After watching a couple of videos on similar transmissions, I understand the blocking rings and how they work. To me, they look new. They have sharp edges but I am still going to take it apart and inspect all the parts. I will deal with the broken shift lever towards the end of the process. Thanks.

 

Blocking rings can look good from the outside, but be worn out. It's the little ridges that ride on the conical surface of the gear that stop gear clash. If you compare a new and used one, you'd probably see a difference. JMO - if I took the transmission apart, I'd replace the blocking rings. The T-15 (in my experience) wears out the blocking rings rather fast, since the gears are big and heavy - for a 3-speed. A lot depends on how fast the previous driver made the shifts, I presume.

 

Yes I saw that they can be worn on the inside as well. It will be worth taking them out for inspection since I never have actually driven this jeep. Would rather check it all out now while I can put the transmission up on the bench. thanks.