I'm part owner on a small freight company and those aren't the numbers I'm seeing. Our current costs are about 80-90cpm on fuel, 65cpm for drivers (60cpm base rate + performance bonuses), about 15cpm for maintenance, and about 15cpm for insurance, tolls, plates, etc. For a total of $1.75 per mile more or less. Before diesel prices spiked the cost of fuel and driver were about even.

The numbers I quoted were post-diesel increase. But it's possible that the numbers are wrong or used a different diesel cost at the height of the spike or were using a diesel price from a really high-tax state or were using a really inefficient truck. The numbers I used would have seen diesel be about twice what you're spending, which is an insanely high multiple. I have no reason to think I'm righter than you, I'm just trying to troubleshoot the reason I was off.

The labor to maintenance/insurance/etc. ratio seems to track pretty accurately. So maybe I should have said 3/6, 2/6 and 1/6 respectively (since the other responder wanted the same denominator).

We're really picky about fuel efficiency. We have aerodynamic equipment on all of our trailers, we give our drivers bonuses on mpg, and also give them 10% of the discount on the fuel cards as a bonus so they actually get on the app and find the cheapest fuel with the most discount. I've heard some fleets have $1+ per mile cost on fuel. Our equipment isn't new though, we bought used 2015 trucks in 2019.

"6/9 of trucking costs is diesel. Like 2/9 is labor, with maintenance, tolls, and other misc. rounding out the last 1/9."

FTFY. Why would you used different denominators, this isn't an algebra test, it makes communication harder for no reason.

The other responder pointed out I was using the simplest terms, which frankly looks right to me. But the answer is more pedestrian. I read the information phrased it as 2/3 was diesel and 2/3 of the remaining amount was labor. So I eliminated the chain and simplified it to 2/3 and (1/3*2/3) 2/9.

I honestly didn't even notice the denominators were different. All of the fractions were in simplest terms, which is (imo) preferable to using a common denominator.