[scatpack_69]

If you can't do an overdrive trans, auto or manual, don't even waste your time. It's pretty much pointless, diesel NEEDS overdrive for any kind of usability. Let's see, Dodge only went with non-OD for a year and a half? There's a reason for that. To have any semblance of highway usage, it has very high axle ratio... which in turn limits low-end pulling power.

I can already hear it, "but diesels have so much low-end torque," yadda yadda. You still can't overcome certain mechanical forces, 400ft-lb and a 2.45 1st gear coupled with 3.73 or 4.10 gears will ALWAYS pull better than the same but with 3.07 gears. Always. Not just from a stop either.

I'm also a fan of lockup converters, slippage in the converter creates heat. Heat is bad. Your trans dies. End of story.

So, you're limited to, in my opinion, the 47RH/RE or 48 RE. The RE versions will cost about 2500-3000 just for the standalone TCM and accompanying valve body, but you have 100% control over every function of the trans. The RH version is fully mechanical, you'll need a switch for converter lockup and another for OD.

As far as a manual, skip the Getrag; NV4500, NV5600, G56. Done.

 

[scatpack_69]

Scatpack you said "The RH version is fully mechanical, you'll need a switch for converter lockup and another for OD.

As far as a manual, skip the Getrag; NV4500, NV5600, G56"

All of these can be used behind a 1st or 2nd Generation engine?

Absolutely. It's been a while since I've looked into it, but I believe for the 47RH you need the second gen adaptor plate and starter. I used to have a great link with pictures of a 47RH swap into a 1st gen (89-93) truck. I'll see if I can dig it up again and link it for you.

Same with the manual trans, just need to correct adaptor plate. Again, I've read some good write ups on swaps, I'll try to link them as well (they were all saved on my old Windows laptop that took a dump.)

 

[scatpack_69]

That one pictured in the Ford is a 12v, mechanical injection. Problem with that Allison is I bet it doesn't have a park pawl, since it's probably air brake-equipped.

Never mind, looked at the pics again, not air brakes.

I forgot about the links, I'll try to remember them.