Looking for advice on specs for a day cab

There is more to it than just the final gear ratios. Tire size, trans, and engine horse power comes in to effect also. My day cab has 11r x 22.5 tires, 10 spd trans, 3.90 gear, 485hp isx15. It takes off great, pulls hills ok, but at 75 mph it's turning 1,800 rpm.

Depending on the height of your trailer, and if fuel mileage is a concern. I'd be looking for a truck with a little higher gear, and fairings. My T880 doesn't have any fairings a high gear, and my end dump is 13'5" tall. I get horrible fuel mileage most of the time is around 4.0 mpg.

 

What!? 4mpg. No one should be that low unless pulling huge oversize.

 

Hauling a van for what?

 

Kenworth t800 or Peterbilt 365 sbfa.
I don’t know where you are and what your bridge laws are to pull 80k. Maybe a 4 axle tractor to gross 84k?
Minimum 220” wheel base, double framed, 475+ on the HP, 18 speed 3.90 rear ratios on 24.5s all the way around. 20k front axle 46ks on the rears. Depending on how far you run I’d put a 100 gallon fuel tank under the driver door and DEF next to it. 50 gallon Hydraulic on the passenger. Batteries under the passenger seat. If your buying new make sure you order it with the truck set up for wet kit already. So they can put the switches in the right area. I hate when I see switches out of place or when someone doesn’t take the time to wire up switches right. They don’t necessarily have to put on the PTO and plumb it if that’s something you can do yourself and save money.
Try checking out Washington Kenworth. That’s where we order our trucks thru. Most are built for logging and heavy haul. Canadian/PNW specs. Goodluck on your build. Remember “buy once,cry once”

 

What the gravel business is like around there I can't say but if its anything like where I am I wouldn't touch a truck without full locker on it. I'd consider heavier rears than the typical 40k lb ones as well as maybe a thicker frame. The gravel trucks where I am lead a tough life and typical highway spec trucks don't tend to hold together for long. If there's a lot of pits and soft mud you have to lift off in loaded I'd go with lower gearing in the rears. Something like 3.73 - 4.10 range.

 

My gosh that tractor would weigh at least 22,000 lbs. To haul a couple ton extra. Thats in average service. Not heavy haul or off road stuff. Think the post mentioned pulling van also. In the 1970s drove a fleetstar IH with a 238 detroit, 13sp, pulled a 28' dump. Light weight 26,500lbs. Grossed at least 90,000 lbs twice a day 6 days a week, on two 150 mile rounds of coal to a powerplant. Saying this to point out it was a regular road trk. Nothing special. Not to say ratings on components aren't important. But the trk will take a lot more than what it's rated for. Just my experience. I may add in 1982 purchased a IH co9670. 4 spring IH suspension. ( like a 4 spring reyco) Pulled dump with it also. Hauled coal, sand , and iron ore. Many 60 to 65,000 lb payloads. Sure i replaced springs, and rear end housing had cracks to be welded, once or so. But drove that trk 1,640,000 miles. 17 years. The speedo showed 640,000 something when i got rid of it. Speedo didn't have extra digit for the 1 mil. Pulled van freight later with it. Now! If i weren't so tech challenged i would post pics on here of it. Even old fleetstar pics, thats another story on driver comfort.

 

I'd get a day cab with a big box on the back with a bed in it.