I recently totaled my 89 F-250 with a 7.3 natural mated to a c-6 tranny. The powertrain is still good, but the body and frame is toast. I have a 74 international 1600 series bus that has been converted to a motorhome, weighing in at about 11k not hooked up to the boat. I'm looking at the 7.3 and thinking that the bus would be a good home for it as the old 345 gasser was seriously lacking. Will the C-6 tranny handle the weight on a regular basis or do I need to seek a manual trans for the swap? Also, if the adapter plate is removed from the 7.3, will the 4-speed in the bus bolt up to it? An OD would be nice, but working on a budget this doesn't always work out.
Understanding that the driveshaft length may need to be changed, will what is there handle the torque of the diesel?

 

The 7.3 would definitely be an improvement over the 345. I'm an IH guy and like the small IH v8s but for that vehicle I'd take an IDI over any of the IH gassers.

You will not be able to bolt up the bellhousing that was behind the SV to the IDI engine(well, not without a custom adapter). You could source a bellhousing that would have the IHC MV(404/446, what the IDI was based on) gasser pattern, the correct depth, and the IHC spec Warner T98/T18/T19 trans pattern. This would also use your current clutch release system as the throw-out crosshafts will swap between the various IHC bells.

The stock Loadstar driveline will handle IDI power.

I'd use the C-6 with a healthy trans cooler upfront but I'm not familiar with the C-6's limits. If it had come with an automatic from IHC, your 1600 would have an Allison AT540.

Oh, other options include sourcing the SAE flywheel housing for the IDI and going from there. Lots of possibilities then, but generally lots of $ too.

You'll also find that this swap will increase the resale value of your IH. Enough to offset the costs if you do the swap yourself. So the other benefits give you that much more reason to do it.

Ken

 

Although I am not an automatic person, I would say the C 6 will be fine with a tranny cooler.

 

Thanks for the input, once I get full use of my legs again, I think that I'll start tearing down the truck and getting ready for the swap-I'm certain that I will have more questions along the way though.

 

My dad had switched out a few manual transmission to the c-6 autos on some 24ft straight jobs (gas) back in the 80’s, had quite a bit of weight them. He got sick and tired of changing clutches - not everyone can drive stick! He used an automatic floor shifter. I can't remember any of the guys blowing the c-6? I know they used to get about 150,000 on the c-6 / 6.9 in the cube vans, and then he'd pull them and rebuild them before they gave out. The cube vans were used mostly to haul spuds and I'm sure they spent they're life at max weight so you should be ok with what you want to do. If you have the transmission out it may be worth a look before you make the switch?