Heya,

I've read alot about one of the hardest trailers to back being a spread axle. I see quite a few, and was wondering why that is, I have a theory, tell me if Im right

I've seen them turn while unloaded and they tend to pivot on the forward axle, does that tend to be true while loaded as well? I really cant imagine it pivoting on the rear axle when loaded, but any insight is appreciated.

Thanks

If the rear axle is dumped, i.e. the airbags depressurized, it will pivot on the front axle, if the rear axle is aired up, it may pivot on either one, they don't back up the same way twice. The ideal setup is to be able to dump either one. If only one I would prefer dumping the front because that puts a bit more weight on the drive axles, and the back of the trailer can't swing as wildly. Loading affects turning in that more weight is on those tires, the trailers I pull are heavy empty or full, but the loads are pretty even, a normal flatbed load might be heavy at the front or the rear depending on what the load consists of. An even load is probably the hardest to back up while turning because both axles would tend to grab on uneven ground.

The main reason for the dump valves is to save wear and tear on the tires, also saves strain on the whole trailer.

Step decks have a short stub axle for each set of duals, they are probably the worst as far as being able to stand the strains involved.

This is the whole reason. If you are backing in on uneven ground then the pivot point changes on which axle is bearing the most weight.

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I've always see the axles want to tear away from the frame on those spreadaxle trailers.

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Z-Lady's devoted hubby.

You would think so, but it happens a lot less than you might think. They sure take A LOT of abuse.

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Wow, didnt imagine there being so many factors, makes much more sense now, thank guys

my personal opionon is if you have a spread, you NEED to have the dump valve wired to a switch inside the cab

if you dont dump one axle in a tight turn (more than 45 degrees) you really scrub off rubber, and could possibly damage the suspension mounts

not dumpin cuases alot of the odd tire wear on these trailers, and i see alot of them with an outside, manual dump......that the drivers never use.

If you turn too sharp with a lot of weight, the front trailer tires go sideways and tear the side walls. If you turn a sharp corner, it acts like a brake, especially when starting up hill. However, the spread allows you to put more weight on the trailer...40 thou compared to 34 for tandems... and is desiged to balance out the load so there's no more than 1,000 lb difference in axle weights.

Then you have the whole lift axle scenario..... Let me confuse you a bit more..... How about these?

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LOAD EM LIKE RAIL CARS, DRIVE EM LIKE RACE CARS!!!!

I see those alot in Gary I have seen them with most all of the axles lifted except a few towards the center

Its just a toy but those are the ones I'd never want to drive, too much damn weight, I've seen them with 2 slabs of fresh steel being hauled down the road to be turned in to rolls, expensive tire bill no doubt.