ExRocketScientist wrote:
This is one of those sneaky little details. The GAWR is not what the axle manufacturer says it is -- it is what the trailer manufacturer says it is, as long as it does not exceed what the axle manufacturer says.
So typically, a D52 shows up with a GAWR of 5000 pounds instead of 5200 pounds. This allows the trailer manufacturer to legally put the ST225/75R15 load range D tire on the axle -- i.e. trailer manufacturers are allowed to derate axles to suit their needs.
In an earlier post, someone (most likely FE) found a trailer placarded with GAWR of 7000 pounds and the tires were rated at 3420 each. As I mentioned, and either Roger or Barry confirmed, this would be subject to recall because it violates the federal standard. All the trailer manufacturer would have to do is issue new placards that indicated GAWR of 6840 pounds and they would satisfy the recall. Of course, there might be an owner who would take legal action over it being derated after the sale.
I think the heart of the problem is the freedom that manufacturers have to manipulate weight numbers to suit themselves. Why on earth aren't they required to actually WEIGH trailers?
Not that weight can't be very closely calculated on the drafting board...
And here's another thing:
By law, "dry weight" numbers must include:
NHTSA wrote:
S4.3.5: If the vehicle is a recreation vehicle trailer and is equipped with a propane supply, the weight of full propane tanks must be included in the vehicle's unloaded vehicle weight. If the vehicle is a
recreation vehicle trailer and is equipped with an on-board potable
water supply, the weight of such on-board water must be treated as
cargo.
Not having looked at labels since this discussion began, I don't know if those numbers are making it onto a trailer label, but I can say with confidence that in most cases that weight is NOT included in the advertised numbers.
In some cases we're talking about four or five hundred pounds, which in itself may put OE tires over their limit.
Add a deep cycle battery or two (weirdly excluded in the regs) and there's another hundred.
And we haven't put so much as a fishing pole inside the trailer yet!
