tooltruckguy

I'm new to towing. When I take my truck and trailer to a truck scale, exactly how do I measure the various axle weights? My rig is much shorter than a tractor trailer?

I'm sure there's an easy answer that escapes me now.

Thanks.

atwowheelguy

I recommend going inside first to tell them that you are going to weigh your rig three times. It costs about $10 for the first weigh and about $2 for each additional weigh. You can go ahead and pay for all three, but if you do, get a receipt. But if there is a personnel change during your three weighs, you may have a problem explaining what is going on to the second person, so hang on to that receipt. DAMHIK. I find it easier to pay for each weight pass each time and just go inside and get the ticket each time when you pay.

There will be three pads on the scale. Put the truck front wheels on the first, the truck rear wheels on the second and the trailer wheels on the third. It's not difficult to do.

Weighing the first time:
Each time across the scale, you will have to get out of the truck to reach up really high to push the button to call the inside person to the squawk box. It will be really noisy there, so you have to shout to be heard and it will be difficult to hear the inside person. Tell them that you are weighing Unit # (Make up a number, I say "Unit # 1"). Ask them to let you get back in the truck before they take the weight.

Weighing the second time:
If another truck is waiting, pull off the scale, go pay and get your first ticket, disconnect the weight distribution bars, and come back for another weighing. If no truck is waiting, and you have already paid, disconnect your weight distribution bars right there, put them in the back of the truck, ask for another weighing. Tell them it's for Unit # 1 or whatever you told them the first time. Make sure you get back in the truck before they take the weight.

Weighing the third time:
Pull off the scale and go park. Go inside and pay for your second ticket and get it. Disconnect the trailer, go back to the scale and weigh just the truck. Again, front wheels on one pad and rear wheels on the other pad. Get back in the truck before they take the weight. Go inside and pay for your third ticket and get it.

Then you will be able to determine your truck weight, your trailer weight, your tongue weight and how much weight your weight distribution bars are transferring to the front truck axle and to the trailer axle.

tooltruckguy

Thanks for the info. It cleared it up for me.

Boulevard

It completely mystifies me why anyone would need a scale in order to set up a truck not to mention that your average truck scale is accurate to =/- 300lbs. I will tell you this much though, the reason that it is so loud inside the scale shack is because the operator just fell off of his chair because he is laughing so much.

atwowheelguy

brulaz

Guess you've never used a CAT scale. That's what we're talking about, and they are quite accurate. They have to be as they guarantee their weights.

As for precision, when I weigh my truck separately with or without the WDH tightened up, the total weights are usually identical, occasionally 20# difference. Very precise. Once, the difference was 40#, but that was because I left the WDH bars on the ground, not on the scale.

Not sure if they are owned independently from the station, but they are maintained independently by CAT. We met one of the CAT scale mobile maintenance teams down in Florida.

smokeywren

In my experience with dozens of trips across the scales with a trailer, the CAT and J scales and other certified automated truck scales are accurate within about 20 pounds.


For example when setting up my Straight-Line WD hitch, the CAT scale weights were
3280 front, 3520 rear and 3620 trailer, total 10,420
with the spring bars tightened. And they were
3040, 3880 and 3480 total 10,400 with the spring bars loose.


So you can see the effects of the spring bars with 20 pounds scale error.


The spring bars added 240 pounds to the front axle, 140 pounds to the trailer axles and subtracted 360 pounds from the rear axle. Based on that weighing, the WD hitch still needed a bit of adjustment to transfer more weight to the trailer axles and less to the front axle, but the weight remaining on the rear axle was about perfect at 50% of tongue weight.