Loading a legal weight into leaf spring trailer

**camaron32** · 07.28.2012

I recently started hauling liquid hazmat (gas, diesel and ethanol). The cab doesn't have a air suspension gauge and the trailer is the old leaf spring style. The pockets are 3500 (at the front of the trailer), 1500, 1500 and 3000 gallons (at the rear of the trailer). Now empty with a full tank of diesel the steer axles are 11080, the drive axles are 11480 and the rear trailer axles are 7620. I know diesel weighs approximately 7lbs/gallon. What I'm asking is how many gallons can I put into each pocket and still have a legal weight. Thank you for your help.

**jbatmick** · 07.28.2012

I do not believe there is any way to figure it out with the info you have. My advice would be to ask other fuel haulers. Sorry.

**rockee** · 07.29.2012

Seems to me like your company would already have this information available to you if they have been around any length of time. If you found your empty weights cant you find your loaded weights the same way?

**daf105paccar** · 07.29.2012

Do you have a teacher friend who is good at maths?

You would have to make a Excell file which you then could check.

If the overhang on the kinpin is the same as the distance from the middle off the 2 traileraxles to the end off the tanker then is realitvely easy to make that Excell file.

You didn't say how much you are allowed on your axles.

**ralph** · 07.29.2012

$100 in parts and labor would solve the problem by having a guage installed for the drives. Are employers really that cheap or are they still stuck in the 70's?

**G/MAN** · 07.29.2012

If you really want to know you can find out for about $10. Just find a CAT scale after you are loaded and check the weights. You could do an empty weight just before loading and that would make it much easier to calculate your actual loaded weight.

**camaron32** · 07.31.2012

Maybe I didn't explain myself well enough. I went to the nearest CAT scale and got my empty weight with a full tank of fuel. I have a 34k limit on my drive and trailer axles like most trucks. The refineries that I go to with my bottom loading compartmentalized trailer use a computer system that requires that you enter a gallon amount before the pocket is loaded. What I am trying to figure out is how many gallons of fuel can I load into each pocket and still be legal. I know that a gallon of gas weighs approximately 6lbs and a gallon of diesel weights about 7lbs. If I overload it it would be a pain in the backside to off load the excess fuel, or I can pray that I don't get picked up by Johnny Law. I could go to a CAT scale, but there is only one in my area and since I do at least four deliveries a day it just wouldn't be practical.

And if I went and spent the money to get an air gauge for the cab, how would that help me determine the weight on the leaf springs?

**ralph** · 07.31.2012

Originally Posted by camaron32

And if I went and spent the money to get an air gauge for the cab, how would that help me determine the weight on the leaf springs?

It wouldn't.

Simple math would though. If your drives show on the guage that your are loaded to the max weight/pressure and that you had loaded the number of gallons that would make a legal load then you should be legal right?

**xaxzax** · 07.31.2012

your question would be an excellent one for either your dispatcher or your terminal manager, both of whom should fuel hauling experience, I hope.

**Rollover the Original** · 07.31.2012

I'm back! More on that later!

What you need to do is get the EXACT weight of your fuels.
NOT about or estimates! If you go on "abouts"/estimates your problem will only get you a larger ticket! When messing with what in your case is an inexact case/mathematical problem under estimating the weight can hurt you and that pay check! As in if the fuel weight 7.8 pounds per gallon and you figure 7.3 and you put in what you believe to be 44,000 puonds but that extra .5 pounds per gallon will put you over weight BUT if you figure 7.3 on that 7.8 per gallon you might be short at the delivery point, your boss might get a tad bit miffed because you didn't "max out" the load and bite a large chunk out of that arse or pay check! Especially if you are paid that percentage!

The old sulfur diesel before the low sulfur mix was 7.3 pounds per gallon. The new stuff I do not know but a quick and unverified check on google shows it to be between 6.951 7.076 pounds per gallon. I do not know about gas as that was never a factor for me when I fueled and was close to max.

I would ask the refinery first then if they have no idea Google "what is the weight of" what ever fuel or chemical your load is and ask a specific nomenclature for a better result, but verify it with several different links and NOT trust the first one to list! The refinery should be able to tell you OR do it the old fashioned way and get a gallon jug weight it on a bathroom scale preferably a digital one and weigh each fuel by the pumps 1 gallon mark.

As another said earlier to use an excel spreadsheet but unless you know how to do those formulas have fun! MS Works has their easy calc which walks you through the process.

Ask the company as they have been doing it for a while. If not then keep a chart OR yes an excel sheet but set it up so that you have it in just rows and columns but with no formulas and after each load and trying different fuels in the pockets you'll get it figured out.

But really ask the other drivers and also learn what routes they take to get to where they need to go as in "running the scales!" NOT that I would tell you to do so but ask the other hands!