I say that the peak torque RPM should be your cruising RPM because it was suggested to me from a friend who has re powered a few trucks, and it has worked well for me and this f350 I just re geared. Hoverer this comes from diesel engines. Knowing that your v6 is a lower speed higher torque engine, similar to the Detroit Diesel I think that the advice is still sound.
3,000 will suck lots of fuel.
I suggest you contact Jolly, the 6066 guy, as he probably has a good idea of what rpm and speed you can run with the engine and size truck you have.
Either you want the v6, or you want a diesel, the reasons for both should be a lot different. What do you want your truck to do, how will you use it? Is the time and effort and expense required to do a non standard engine swap like the 5.9 going to pay off for what you need?
I think that the 5.9 with turbo and intercooler is a great engine, and the NV4500 is possibly the best transmission smaller than a Roadranger RTO6610, although I have next to no personal experience with either.
I am a big fan of the Detroit Diesel 53 series for pickup sized conversions, mostly the 4-53T, although if economy and not speed are your priorities then a 3-53T is good. And for a serious truck, with a front end to hold it, the 6V53T is nice, although arguably to big for a 1 ton. The Detroits are different, simple, strong, and reliable. The RTO6610 overdrive 10 speed transmission is a great addition to the Detroit for a working truck, an NV4500 would be good for the daily driver with not so much hauling.
You mention 10 lug 20" rims for a newer ford super duty, are you sure they make such a thing?
I believe they only come up to 19.5", and an 8R19.5 tire is about 33" tall. If you are talking about the original super duty's from the 80's the wheels for the 10 on 7.25" with 5.46" center hole are only available up to 16 or 16.5, I forget. However, the 19.5" Chevy 3500HD wheels can have the center holes bored out to fit the ford hubs. With the Chevy axles you can find used 22.5" wheels to fit, not as easy, or even possible for the ford unless Rickson truck offers them.
I think that the better choice for that size axle is the 3500HD or P30, and not the ford. I have done two axle conversions, both times looking at the 3500HD and super duty as potential donors. I decided on and used the 3500HD for one and it worked great. The second one I went with a Chevy 4500 topkick axle.
I have pictures of both swaps and some Detroit Diesel 53 series on my link below.
What do you really want your truck to do?
Grigg
