Question about gearing
So we finally took a long trip with our new rig, which performed better than expected. Coming from a diesel tow rig to a gas tow rig was a bit of a culture shock; the high revving 6.0L does the job bu...
Forum Discussion
BEST power per say for your motor is where the torque and hp curves cross in Bens Diagrams. ABout 2500-2800 as noted. "IF" this were me, I would shoot for this rpm in 5th, and then in the 3000-4000 rpm range in 4th direct.
As far as which gearing is better......neither, or as it is sometimes called, "IT DEPENDS" My navistar is a direct drive trans, I have to use direct as some use OD. I also need a much lower first gear to get me going vs if using an OD trans. One time I compared a 3.42 geared rig with a 4sp direct drive manual, and a 4.10 geared 5 sp manual. Generally speaking, both had the same overall low, same overall high ratio rpm at 60. As in old days, "gear it fast, run it slow" ie a 3.08 gear ratio in direct, or "gear it slow, run it fast" ie a 4.10 gear rig with a .75 OD is doing the same rpm at 60, 65 etc.
Chose poison. At the end of the day, the best ratio is based on tire diam, speeds you drive, and rpm that is best for YOUR engine at those speeds. This is what the gear ratio should be for, not a bogus "engine/gear ratio" tow rating.
Marty
As far as which gearing is better......neither, or as it is sometimes called, "IT DEPENDS" My navistar is a direct drive trans, I have to use direct as some use OD. I also need a much lower first gear to get me going vs if using an OD trans. One time I compared a 3.42 geared rig with a 4sp direct drive manual, and a 4.10 geared 5 sp manual. Generally speaking, both had the same overall low, same overall high ratio rpm at 60. As in old days, "gear it fast, run it slow" ie a 3.08 gear ratio in direct, or "gear it slow, run it fast" ie a 4.10 gear rig with a .75 OD is doing the same rpm at 60, 65 etc.
Chose poison. At the end of the day, the best ratio is based on tire diam, speeds you drive, and rpm that is best for YOUR engine at those speeds. This is what the gear ratio should be for, not a bogus "engine/gear ratio" tow rating.
Marty
