Tri Axle loads and gear ratio

Hello,

i have a question regarding pulling Tri Axle loads (containers) full. What gear or axle ratio do I need for a truck to pull it smoothly? Im a volvo fan and I see how some only have a 2.64 ratio. Is that enough to pull heavier loads? I get mixed answers from some people but maybe more experience drivers can help here! Pls explain how this ratio thing works! I will do local work, no hills or mountains just flat land basically. Any info helps!

 

Generally a standard highway truck will do fine on paved highways. If you do a lot of gravel or off road work then a heavier spec’d truck would be required.
We had a guy pulling 140,000 lbs with 3.23 rears and he did okay.

 

It's confusing, but the higher the number, the lower the ratio. For example, a low ratio( high number), say, 4:11, is for off road, heavy duty, and the 2:64 you mention, is a high ratio,( low number) meaning higher speed or economy, but not good for pulling. I pulled containers, and some are quite heavy, and I don't think a high ratio will work unless you like replacing clutches. I'd suggest something like a 3:55, and a big Detroit motor. For years, a 3:90 was the best all around ratio for the small motors we had.

 

A modern truck with 2.64 ratio will do fine with heavy loads running on the highway. It’s probably paired with a 12 speed auto and won’t have any issues with startability.

 

How much weight are you pulling? What engine is in the truck? If you are talking about a Volvo engine what one are you looking at the D13 or D13TC?

If 80K and with either engine at 2.64 would be ok and have no problems. More details and can help better.

 

100k i assume. D13 2019, 2.64. 13200 front 40k rear

 

You would be fine but you will want to make sure that your start gear is set to 1 in the parameters. With the D13 not the D13TC you can have them bump the HP to 500 and that will help as well.

 

Ok thats good to know!

 

You have multiple gears in that transmission to choose from. A truck that’ll pull 80K will pull 97K. The truck you’re looking at will pull that container, with zero issues. You may not be able to run 12th gear everywhere, but, that’s why the transmission has an 11th gear and manual mode. The payoff is being able to run a lower RPM, when light or empty, resulting in better fuel economy.

Only vocational stuff need the really low gears, because of offroad use at jobsites, quarries, etc.

 

I have said this before and people don’t believe me or don’t understand but the low numerical ratios like 2.64 are hard on drive shafts and clutches especially when starting that load out on a grade. Any kind of off road with that ratio is looking for trouble with a good load. Not saying it’s not going to work and once you’re rolling on the highway it will be fine.