according to NHTSA/FMCSA, GCWR is a legal term but it is not at this time a fed requirement to be on a placarded (door tag) on our vehicles. But the term is used in other areas involving trucks and trailers.
Subpart A—General
§ 571.1 Scope.
This part contains the Federal Motor
Vehicle Safety Standards for motor vehicles
and motor vehicle equipment established
under section 103 of the National
Traffic and Motor Vehicle Safety
Act of 1966 (80 Stat. 718).
33 FR 19703, Dec. 25, 1968. Redesignated at 35
FR 5118, Mar. 26, 1970
§ 571.3 Definitions.
(a) Statutory definitions. All terms defined
in section 102 of the Act are used
in their statutory meaning.
GCWR
Gross combination weight rating or
GCWR means the value specified by the
manufacturer as the loaded weight of a
combination vehicle.
My state also uses GCWR terms here:
Oklahoma Statutes Citationized
Title 47. Motor Vehicles
Chapter 1- Definitions of Words and Phrases
Section 1-120.1 - Determination of Gross Combination Weight Rating (GCWR)
The value specified by the manufacturer as the loaded weight of a combination or articulated vehicle. In the absence of a value specified by the manufacturer, the gross combination weight rating shall be determined by adding the gross vehicle weight rating of the power unit and the total weight of the towed unit and any load thereon.
Now, being that its not a door tag requirement, how is the term used. One way GCWR is used is for our commercial haulers. Their 3500 DRW, for example, has a 11500 GVWR and their 32' flatdeck GN has a 16000 GVWR which gives them a 27500 GCWR. That GCWR is used to buy their combined tag/plates for their combination truck/trailer.
There is a push to have NHTSA require GCWR on the door post according to NHTSA home page. Boy would that get more weights threads going.
Jim
'03 2500 Dodge/Cummins HO 3.73 6 speed manual Jacobs
'97 Park Avanue 28' with two slides
JIMNLIN wrote: There is a push to have NHTSA require GCWR on the door post according to NHTSA home page. Boy would that get more weights threads going.
There is also an initiative under way by the SAE to determine a fixed method for determining tow rating (and thus GCWR). {Source}
The NHTSA cannot, will not and should not recognize a rating that has no known origin. Since the news of the SAE initiative surfaced last fall, I've been unable to find any information on the outcome of this committee, but I expect it will be a slow-moving process.
It also (at this time) is only looking at pickup trucks. Clearly this is because the OEMs have pushed this segment well into skeptical areas by continually increasing ratings with little or no technical merit.
'04 Ford Freestar (Primary tow vehicle) '05 Subaru Forester (Backup tow vehicle) '65 Bethany popup (best popups ever made!) Looking for a tow vehicle Minivan towing
Caddywhompus said: " ... Clearly this is because the OEMs have pushed this segment well into skeptical areas by continually increasing ratings with little or no technical merit."
And the reverse is also true. There are vehicles that are markedly under-rated just so the marketing arms of the manufacturers can have a technically differentiated product line to sell. Bodies the same, frames the same, drivetrain the same, everything the same save a couple of overload leaves that the aftermarket can address for a couple of hundred dollars or even less. It's cheaper for the manufacturer to make one vehicle and sell it in two supposedly different segments than it is to engineer two completely different trucks.
Additionally, I wholeheartedly agree with Caddywhompus when he says: "The NHTSA cannot, will not and should not recognize a rating that has no known origin." A DOT rated item is different inasmuch as there are defined standards that must be met in order to achieve the rating, and those standards are identical for every manufacturer.
pupeperson wrote: Caddywhompus said: " ... Clearly this is because the OEMs have pushed this segment well into skeptical areas by continually increasing ratings with little or no technical merit."
And the reverse is also true. There are vehicles that are markedly under-rated just so the marketing arms of the manufacturers can have a technically differentiated product line to sell. Bodies the same, frames the same, drivetrain the same, everything the same save a couple of overload leaves that the aftermarket can address for a couple of hundred dollars or even less. It's cheaper for the manufacturer to make one vehicle and sell it in two supposedly different segments than it is to engineer two completely different trucks.
Additionally, I wholeheartedly agree with Caddywhompus when he says: "The NHTSA cannot, will not and should not recognize a rating that has no known origin." A DOT rated item is different inasmuch as there are defined standards that must be met in order to achieve the rating, and those standards are identical for every manufacturer.
The problem as I understand all the arguments is that the GCWR has no legal weight. But it does have a great deal to do with whether a vehicle can accelerate onto for instance a freeway towing a specific load. I know for a fact that in PA there are a lot of freeway on ramps that are very short and trying to drag a load from zero to 65MPH trying to merge onto a freeway in those cases could be nearly suisidal . In those cases the NHTSA should be involved to provide the guide lines for all vehicles capable of towing to ensure that they can safely accelerate onto freeway on ramps in a safe manner. That is one of the reasons I choose to live within the GCWR/GVWR of my vehicles. YOU need to make the choices for yourselves what you want to do to protect you and your family.
The problem with staying under GCWR per manufactures ratings, does NOT say that they, ie the manufacture and there rating, has taken into account the ability to accelerate up said freeway ramp to meet speed in that amount of time!
This goes back to my, why is my Navistar dumptruck with a 170HP/336 torque rated to 35K GCWR, yet my 05 3500 dually with a 300+/600+ motor is rated to 23500? Trust me, at 25K lbs which I have had the 3500 at accelerates way faster than the Navistar. In fact, many times the navistar would not meet your requirement for acceleration at its max GCWR! In fact, one has to also know, that in reality, my truck, while it does have a 35K GCWR, was never ment to be used beyond GVWR, ie 19K lbs! Many MDT's are speced this way by the dealers that order them, knowing most folks will put a box van on them, maybe a flatbed and they will NOT tow a trailer! Hence, in reality, the GCWR is a non issue per say.
THere is way too many ifs ands or butts if you will behind "WHAT" does GCWR stand for. For some like you, it is how fast I can accelerate to 60mph if that is the way you want to go. For me, if I can not pull a 30% grade at GCWR then it is not really rated to that amount. With this in mind, my 05 3500 dually, is NOT really rated to 23500, as I can not even pull 30% at 20K lbs, it is more like 24-26% at 20K lbs. SO it is under powered, or under geared in the trans/axels in my case! I can pull 25K up a 4% grade at 60 mph, but who cares if I get to a job site with my rig, and can not pull up that last 200 yds because there is a driveway that is 30% in grade! I'm stuck! Blowing up a trans as I did with my old 89 3500 dually with a 454, th400 trans and 4.10 gears! Supposidly could pull any mtn in front of me. Yet the 105HP 292 I6 power 2500 with 4.10's and a muncie 4spd, yeah the one with a GCWR "LESS" than its GVWR, went up the hill at 12K, came down hooked a chain to the 12K GVW dually, and pulled it up the hill! Double its GVWR/GCWR rating. On my current 3500, I would take something that pulled a 4% grade at 50 mph, if I could get the correct gearing in the trans and axels such that I could pull a 35% grade at 20K, and 50 mph on a 4% freeway grade! A much better set up rig for my use than my current POJ DA combo!!!!
GCWR until the manufactures tell us what goes into there respective ratings, are useless items for some of us! It does NOT give you what is safe, what it can do performance wise. Then you have the, are you pulling a 70# frontal area trailer, or a 90# frontal area trailer. At 60 mph, a 70# FAR setup and 15K lbs needs 105 HP to go 60 on a level. A 90# 15K rig needs 135HP, same HP as a 25K lb rig with 70# of frontal area! "WHERE" in the GCWR ratings is this taken into account? ANother, the truck trailer aerodynmics can vary that HP needed by +- 35% depending upon how rounded, or flat faced or in the case of those of use with pipe racks on trucks will also loose power availible to motor down the road.
There is NO simple answer, other than to keep yourself with in legal paid for license, under your axel wt requirements per fed and local state law. Otherwise, the manufactures GCWR is only good for warrenty items only! That is also per three local WSP Weights enforcement officers that I have taken classes from to make sure my company keeps its trucks and trailer with in "MY" states laws.
Marty
05 Chev CC D/A LS Dooley
92 Navistar dump truck, 7.3L 7 sp, 4.33 gears with a Detroit no spin
00 Chev C2500, V5700, 4L80E, 4.10, base truck, no options!
92 Red-e-haul 12K equipment trailer
3 Single axle utility trailers
Ductape wrote: GCVWR from the Mfr.'s viewpoint is just a measure of what
they can rate the vehicle at and get xx% of the fleet past the warranty period.
If true, then going over that GCWR will cause them to not make it to
the warranty period...and I do prescribe to this line of thinking.
As Marty says, there is no simple answer and way too many variables.
I think too many associate what they 'see' on the various GCWR charts
as representative of what matters...kinda sorta yes, but that is just
the weak link and that there are many other links not visible but
important.
So moving up in weight will/might expose another link as the weak one.
Will it be the brakes? Tranny? Axles? Frame? Who knows?
The OEM's will *NEVER* disclose their data on these, as then they
will have a basis for those suing them to sue'm more effectively.
Over all a good discussion and hope at least one person will take
the time to review and *decide* on their setup based on whatever
metrics they deem...
-Ben Picture of my rig
1996 GMC SLT Suburban 3/4 ton K3500/7.4L/4:1/+150Kmiles orig owner...
1980 Chevy Silverado C10/long bed/"BUILT" 5.7L/3:73/1 ton helper springs/+329Kmiles, bought it from dad...
1998 Mazda B2500 (1/2 ton) pickup, 2nd owner...
Praise Dyno Brake equiped and all have "nose bleed" braking!
Previous trucks/offroaders: 40's Jeep restored in mid 60's / 69 DuneBuggy (approx +1K lb: VW pan/200hpCorvair: eng, cam, dual carb'w velocity stacks'n 18" runners, 4spd transaxle) made myself from ground up / 1970 Toyota FJ40 / 1973 K5 Blazer (2dr Tahoe, 1 ton axles front/rear, +255K miles when sold it)...
Sold the boat (looking for another): Trophy with twin 150's...
51 cylinders in household, what's yours?...
BenK wrote: take the time to review and *decide* on their setup based on whatever
metrics they deem...
Way to much Gray area for my comfort.
But that is where we are at.
JMO
And that is why we'll get legislation to control this area after
one too many accidents/issues/etc from those who will push it
to the limits and beyond. It's a free for all in GCWR till that day
This is the way of it...speed limits, proper class of components,
driver testing (eye sight, knowledge of laws, etc), insurance, etc, etc
A guy from Finland asked about class of tires for his Suburban 2500
on our Suburban forum. Sent his wife to get new tires and the tire
shop installed "P" rated tires. He took our discussion print out over
the tire shop and the owner agreed that his guys messed up and installed
"LT" tires at no cost. Same size, just the next higher class tire.
Confirmed that over there, the legal system would fine his business,
maybe revoke his biz license and even jail time if an accident
happened and even it the tires were not the cause, once the
inspectors went over the vehicle and found lower class tires. Even
jail time for the owner and impound the vehicle and not allowed to
move from the spot where they discovered the issue. Wished our
government took these things more seriously or had the teeth/guts to
enforce'm.
Then marketing/sales will get involved with 'King of the Hill' brag
on GCWR and the attendant fine print.
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