Hey guys new to this forum and figured this would be a good place to get help with my build.... Im taking a 96' cummins out of a bus and putting it in my 2000 chevy k3500 with a VN4500. right now the truck has a 7.4 vortec in it with an automatic trans in it, and I plan on keeping the pcm in it to make all the factory guages work properly. But the point of this post is I have a few questions.

Where and how is the the tach out put hooked up for RPM reading.

Anyone running a 4:10 gear behind there nv4500 hopping it doesnt make first gear useless unless your pulling a house down and what kind of rpm are you seeing running in the 60-65 mph range.

Also I will be either setting the engine up or doing it all at once but I'm looking to make as much power as I can while the truck still gets the best fuel economy and can still pull a trailer with out running my egt's through the roof with a heavy load.

Any help with these questions or any more in the future are greatly appreciated!

 

Even with 3.55's, unless you're towing, first gear is still worthless. Everybody I know starts out in 2nd gear. With 4.10's, 2nd gear is still going to be pretty low.

 

i was afraid of that. and my tire would probably be a 285

 

How heavy and how often do you tow? 3.55's should still tow pretty good, but if you need something lower than that, you might consider 3.73's.

 

usually never more then a deckover or car hauler with a full size pick up on it, and maybe twice a month. ive decided that i do need to swap the gears out but the 4:10's will have to work for a little while as im not gonna have the extra money after doing the swap. but to what gears idk not sure what gm offered between a 3:73 and the 3:08 i believe it is.