My coupe has a 91 3.9 V6 with an AX15 5 speed. I'm currently running the early 90s throttle body injection.

This motor has around 170,000 miles and is showing its age. Last year, the rear oil seal started leaking, I didn't know until it was tore apart it had a rope seal. According to what I've read, you can't replace the rope seal without removing the crank and pressing the new rope in place. The rope seals are pretty hard to find these days. As it was, I removed the rope seal and installed the standard replacement seal, and sure enough, it leaks worse then the old rope seal leaked.

We have made it through another driving season, so once again I am facing that rear seal again. Currently the motor is going through about a quart in 500 miles, most of that through the rear seal, but it also has a hint of blue exhaust. and the famous blue haze valve seal leak on start ups.

Good used 3.9 are hard to come by around here. Rebuilding the one I have is an option, but I'd rather not go that route if I don't have to. This is the 2nd 3.9 in this car, the 1st one would have been better to rebuild, but its long gone.

Both the 3.6 and the 3.7 V6s are readily available here. Will either bolt up to my AX15 trans and bell? Then will one of those motors be adapted to run off the throttle body EFI, and would it be worth the effort? This car has been driven 100,000 road miles in the last 12 years, I am no opposed to installing a more modern V6, but I would really like to keep a standard trans rather then an auto trans. I am also not opposed to upgrading the EFI system if it can be done without all those modern interconnected things I don't have, the current system was from the 90 Dakota donor with 200K miles on it now.

I'm not interested in installing any V8 (hemi or SB Mopar), the car is light, and I'm getting old. The V6 with the standard stick shift is about all the thrill I can handle anymore.

Thoughts and suggestions?
Thanks Gene

any thoughts about a reman long block, from say, Jasper or other source ?
i don't have a clue what something like that would cost, or even if that is available.
just a thought that popped through the cobwebs in my noggin.

I will look into that, but I thought those placed catered mostly to current motors, Didn't the 3.9 pretty much go away in the mid 1990s?

the 3.9 has the bell housing pattern as the LA.

Near as I can find only the 3.9 V6 works with that pattern.

You can always make an adapter.

Somebody here, I think they work for diablo sport built a '72 Dart with a 3.6 and I _think_ a manual transmission. He built it to be a corner carver. I cannot think of his screen name right now. You might search '72 Dart and 3.6 and get a hit?

My 2002 Dakota has a 3.9 with 250,000 miles on it. Still gets me to work every night. They should be out there.

Found him!

on moparts: myduster360

forabodiesonly.com linky

As the link suggests, he's got a T5 behind the 3.6

On the strip

That was an interesting read.

Looks like I need to find a wrecked Jeep for the 3.6 drive train and the other needed parts. Non-wrecked Jeeps are out of my price range. Even then, sure loos like a lot of work & money.