How to weigh axles on a scale that only gives you gross weight?

Yes, your idea will work, but many scales don't allow you to back up on the scale, all motion must be forward. So I would 1) drive and put steer axle only on scale and record the weight. 2) pull forward so steer axle & drive axle is on scale and record weight. 3) put steer, drives, and trailer tandem on scale and record the gross weights.

Steer weight is #1
Drive axles is #2 - #1
Tandem weight is #3 - #2

The problem is if the scale has a steep slope before & after the weight platform. Having parts of the combination sloping up or down from the platform can throw off the math. If the scale and the ground in front and before the scale are roughly level then the weights & calculations are as accurate as the scale itself. Not all scales are accurate. Companies can choose to have their scale tested & certified, but they aren't required. Scales open for public use are required to test & certify yearly in every state I've been to.

 

"I slid both the 5th wheel and the trailer tandems all the way forward, and the drive axles still weighed 34,520 pounds."

The only choice is go back to the shipper and have some of the weight moved more to the rear of the trailer.

 

I have to ask why you could not weigh just the axles at the shipper using (more or less) the way you described, or better yet the way others have described?. Steers, drives, tandems. Was this rolls or pallets? What we use to do, and this is not really recommended, is go in reverse and hit the brakes to slide the load to the rear. But if the pallets are not shrink wrapped good that could be a mess, or as one of our drivers found out, if you are not careful your doors might be bulging if you over do it lol.

 

Does anybody really get hassled for 520lbs? Or is everyone to scared to risk it?

 

There's still guys who have a coronary if they're over 12k on the steers.

But yeah, almost every state will let get by with that as long as you're not over gross.

 

I wouldn't worry about 500#.

Unless your tanks were empty.

 

Yeah. That's what I did. I said that in the OP.

 

If the air on the tractor is at 58 psi I’m real close to 34k ,usually just roll with that. Livermore scales on 580 pretty easy as long as your under 80k

 

At a mill? Not only would I have ran that, if I did have to go back it would of been for more, not less

I recommend a set of pressure guages for the bags so you can load right there