I agree with Reg that there should be more allowance when overloading your tires.  But from an Engineering POV  something that may have been designed that way is that the tires listed on the sitcker would be the first to fail before you cause serious damage to your axle.  I would think tires are less expensive than replacing bent/broken axles. Just my thoughts.

Kevin

reg, you "to the contrary", i dont believe it. i do enjoy other points of view though.

allow me to elaborate.....a tire rated at 3042 and running about 3750 is about 125%, i personally wouldnt expect much service from a component at that stress level. that being said this next part would probably be better explained by a tire rep than my sorry truck driving butt, but here goes......

the reason i said the overload would cause regular blowouts is that in the tire world it is common practice for a tire with a rating of 1/3 the GVWR to be used, this is in case of a blowout. in a blowout the 3 remaining tires have to support the additional load. if they are not of sufficent rating, say they are the GVWR /4 then they will be overloaded by about 33%. this will cause internal damage and contribute to a tire failure. if all the numbers are correct in the OP, this would be another case that appears to back this theory up.

get a hold of a tire rep, theyre more than happy to talk to anyone, (and would likely make more sense than i have), especially after the firestone/explorer situation.

WHOA...  I think you're gonna need a bigger boat...

If you are saying 18000 as GVW and 14.5 - 15k as "axle weight"... are you thinking that 15-20% of the 18k is carried on the truck? therefore, the tires, wheels, axles are expected to ONLY carry 15k?

So you have 3 axles RIGHT?  in which case you should be okay.    If you only have 2 axles and 4 wheels/tires... you are WAY underaxled - and yes, you could well be overflexing one or both axles which is causing horrible stress on your tires.

18k divided by 4 wheels/tires = 4500 pounds per wheel/tire and at LEAST 9000 pound axles.  Now then... you know how sometimes one axle kind of "floats" momentarily?  that's when you need a little extra because as someone else explained, sometimes 3 or perhaps even only 2 wheels/tires are carrying the entire weight.  Therefore using the gvw is necessary.

well not exactly, on the trailer there should be a sticker listing the GVWR and GAWR.  you state the "cat scales weighs the trailer @ gvwr of 18000 lbs" the scale will not give you the GVWR, it will give the GVW.  which appears to be 5800 + "over 14000" = 19800.  how many axles do you have and what are they rated,  you said 7000 in another post.  you look to be over weight in this siuation, so as for the tires, if you do in fact have 7000 axles with tires rated at 3042 you dont have the full 7000 capacity.  using tires rated to 3500 would help, so would taking some weight off the overloaded trailer.  if you use tires rated over the 7000 axle that would probably help the blowout situation, but the axle itself is still overloaded.  premature wear should be expected.

Been gone  a few days....

 If the tongue weight (TW) is 5800 pounds, on the scale, and it's a GN, let's say that represents 25% of the total weight of the trailer. 25% is one-fourth, so 4 times 5800 = full weight (23200 pounds) ???? is this right? Then, less the tongue weight, equals towed weight. That's still 17,400 pounds sitting on 2, 7000 pound axles.   

I'm gonna say that the numbers just don't add up. Hello? Trailer Company?  Come get your unsafe, illegal trailer and give me my money back. Plus, all the money I spent on tires and repairs and down time and aggravation.

Or - this could be a matter of a stripped down trailer having LQ added that made the trailer exceed it's GAWR....

uh what?  no those numbers dont add up,  im pretty sure you cant reverse engineer a trailer weight with the tongue wt. due to the fact the tongue wt % is not a fixed number.

with a tongue of 5800 and axles of 14000+ that is the towed weight of 19800+ and the tongue of about 29%, which would be in line with an overweight trailer.....possibly caused by to many goodies in the LQ.

im really curious about this situation, are the 7000 axles being misread?  possibly 9000?  is this a 3 axle 7000 rig?  how in the world did they reach GVWR of 18000? and who are they?

if none of the above, what is in this particular 4h trailer that causes such a high loaded weight? i just cant see how any of this makes sense.

thats true, but im still curious.

yeah, me too...

but... for those who read and lurk and like the entertainment, I thought I would play around with the numbers some more...

I think it's one of those deals like MBRA suggested.... maybe a late 1990s or early 2000 trailer by a well-known manufacturer (whose name begins with an "E") before they got their guano straight.

We have a Winnah!!!   Door number 2.