Axle weights

You have spread to be able to scale 40k on the trailer. That’s why it’s there.

 

Next time you get loaded heavy and hit the scale, get your fifth wheel where you want it so your tandems and steer are nearly maxed out. Then you'll probably never have to slide the fifth wheel again as long as you're pulling a spread. The extra 6k on the trailer axles makes it really easy to position a load and not worry about being over on a group. So when in doubt, load heavy on the trailer.

Get a set of gauges for the truck and trailer as soon as you can. You can rig them up yourself. Buy two air pressure gauges. Put one on the truck bags, and one on the bags from the front axle of the trailer. That way if you add a dump valve to the rear, you'll still have gauges on the trailer. Then start writing down your psi at the scale, and you'll get an idea what your max weight on each group psi is. After a couple scales, you'll never have to scale again. For example, I haven't scaled since the beginning. My spread is 36,800 at 66psi. I got loaded with mulch, and my gauge was at 82psi. So I rolled over the on site scale. I weighed 88,000 gross. Now they claimed the mulch weighed 41k, but it really weighed 60k. If I had trusted them, I could have damaged my equipment, or got a ticket. But I trusted my gauges, and they worked.

 

Since it's hard to go over a group with a spread, you don't need any fancy gauges on your combo. Just a couple twenty dollar air pressure gauges. Because you'll only be looking at them on loads you think are questionable, and the rest of the time, you'll ignore them. So I wouldn't spend a lot of money on that if I were you.

Yes, there's only one ride height valve, but you will have equal air pressure in all four bags when not using the dump valve. The times it's inaccurate are when the rear axle is dumped, and the system has to put a lot more air pressure in the front bags to try and maintain height. In cases like that, just let the rear bags fill, and drive forward and backward. Then set the brakes and go out there and look. When I'm getting into position to get loaded, and have the rear dumped, I kill the dump valve when I stop, so when they're done loading I can get an accurate reading. Keep in mind as they load, the bags need more and more pressure. So if your air pressure drops to say 60psi, then the gauge will max out at 60psi. In a case like that, you need to air the truck back up before you get an accurate reading.

Sounds complicated, because I'm explaining it badly. But it's really simple.

 

Mount the truck one behind the bunk angled toward the left and beside the pogo stick. Most people stand in that general area when loading so its easy to glance over and see. I like the trailer gauge there too but most times it's back by the dump valve just for ease of plumbing. As long as the ground is relatively level you will get accurate readings. And don't forget about the air pressure in the truck having to be up! Been there done that lol should be under 100 bucks to install 2 liquid filled ones with plumbing etc

 

A common fallacy. 80,000-34,000-34,000=12,000 maximum steer axle, right? Wrong. Most states allow up to 20,000 steer axle. Of course the axle and tires need to be rated, but it's not 12,000 just because that's all that's left.

 

True.....but you can bet if you pull on a scale with 18000 on your steers....you’re going round back to be checked.

 

I know, but there is still lots of 12K front axles out there, and it wasn’t relevant to the question at hand.

We run a 14 K front axle and a three axle trailer around the PNW at 90K, but that’s not helpful information to the OP, since he’s not operating in over 80K states.