best cruising RPMs

[blazinzuk]

For a 6.2 non turbo? I in the past when I have done this with an underpowered motor have tried to set the cruise RPM to as close to the peak torque numbers as possible.

A stock 6.2 makes peak torque at 1900 rpm. If I run 4.56s gears and most any major brand of 35" tire, it puts me just over 2000 rpm at 65 and about 2300 at 75.

Just wondering what you guys have had luck with as far as stuff like this goes

 

[longbedder]

1800 RPM is the generally accepted magic number for these engines. I'm right there (1791 RPM @ 65MPH) with lockup OD trans (700R4), 4.10 gears, and 35" tires, and it does quite well.

That sweet spot does not shift much between naturally aspirated and with a Banks turbo - maybe 100 RPM or so, but it's in the noise.

 

[blazinzuk]

So... I will be a bit off then. The axles I just picked up have 4.56s in them. Thats ok though because I eventually want to run 37s on this truck. Although I doubt I will do that with a 10 bolt in the rear, but I will more than likely retain the 10 bolt in the front for a while

 

[KirsL]

I'm running 4:56s and 35s with a 700r4 and it does turn 2000 at 65 and 2300 at 75. Now while it is loud (I have no carpet in mine at the moment which doesn't help) the truck still gets 16 mpg when I DD it. I thought about doing 4:10 but when I figured I maybe going to 37s one day and that I also tow sometimes (5000lbs), the deeper gears are nice to have. Makes the truck real peppy in town too. I could do all this with 4:10s too but I like having the extra ummph off the line, it's easier on the trans too. If you're going to be on the highway a real lot I would go 4:10s but many for engine noise. Mileage will be pretty close between the two gears sets.

 

[blazinzuk]

This is my daily driver but on highway trips we will usually take our car, so its a mostly in town. I live right off a main highway but the speed limit is 65 so the vast majority of its life it will not go faster than 65.

The longest trips I will be taking in it are for mild trail runs. Probably take it Moab a couple times. I like to go to Montana to wheel too. But that will be loaded up for camping so I don't mind going 60-65 to get a bit better mileage

I got the 4.56s partially because for local runs till I get my dually running, this poor unfortunate soul will be towing Horton.

 

[longbedder]

This is my daily driver but on highway trips we will usually take our car, so its a mostly in town. I live right off a main highway but the speed limit is 65 so the vast majority of its life it will not go faster than 65.

The longest trips I will be taking in it are for mild trail runs. Probably take it Moab a couple times. I like to go to Montana to wheel too. But that will be loaded up for camping so I don't mind going 60-65 to get a bit better mileage

I got the 4.56s partially because for local runs till I get my dually running, this poor unfortunate soul will be towing Horton.

You'll be fine.