Curious about GAWR

[stevegilmore]

Listed on the door of my truck I have a front GAWR of #3525, and my rear GAWR is #4050. So why is my GVWR listed at #7000 and not 7575?

[wulfraat]

This is a source of great debate

The main reason (my understanding) is that although your axles are individual rated, GVWR is set by the manufacturer based on the entire "system" (in theory) - engine, transmission, suspension, brakes, frame/unibody construction, % safety margin applied, etc..

That being said, GAWR is arguably the most important factor (IMO) to ensuring you are not overloading axle, suspension and most importantly (arguably) your tires.

For example, I have a 2017 2500 GMC 3/4 ton class truck. I regularly operate above GVWR but still well within by axle ratings and CGVWR of TV+trailer. In my case GVWR is 10,000 with front axle GAWR @ 5200 and rear @ 6200 GAWR making for 11,400# total. I tow at 4600 front and about 5700 rear loaded / hitched which is 10,300#. I am still a healthy 500lb under my rear axle rating so I don't even sweat it. My tires are rating for > 7,000 lbs @80psi in the rear.

Literally the only difference between my truck and the 1 ton version (now that I have upgraded tires) is that the 1 ton has an additional helper leaf spring that adds 800lbs more WR to the rear axle, bringing it to 7,000# GAWR in the rear. Brakes, engine, transmission, differential, axle housing, etc are all the same otherwise.

So in my case the 1 ton simply squats a little bit less, maybe 1/2-1" @ 5700 lbs on the rear axle. I will probably add some air bags this winter to pull that black in a bit / provide for a little more suspension travel under heavy load (but have no plans to exceed my front or rear axle ratings).

When I towed with my infinity QX56 1/2 ton SUV, which had a 7500# GVWR, we regularly towed at 7750- 8000# on the TV loaded / hitched but with weight correctly distributed across the axles, so I was always under my axle weight ratings front and rear.

Everyone needs to make their own call on towing near, at or above GVWR.

[GeeSag]

Has anyone heard or been able to substantiate:
Manufacturers of 3/4 ton set the limit to 10,000 to avoid states where going over 10,000 changes the classification and the licensing requirements of the vehicle.
Seems 10,000 is an awfully arbitrary number.

[ROBERT CROSS]

I have always used my tire and axle ratings, payload is such a moving target.

Bob
🇺🇸

[BayouBiker]

Originally Posted by GeeSag

Has anyone heard or been able to substantiate:
Manufacturers of 3/4 ton set the limit to 10,000 to avoid states where going over 10,000 changes the classification and the licensing requirements of the vehicle.
Seems 10,000 is an awfully arbitrary number.

Yes, this has been confirmed. It is a known and popular marketing strategy for 3/4 ton trucks in particular. 10,001 is also the point where DOT weight and time journal requirements kick in.

[jcl]

Originally Posted by stevegilmore

Listed on the door of my truck I have a front GAWR of #3525, and my rear GAWR is #4050. So why is my GVWR listed at #7000 and not 7575?

The short answer is that the vehicle is sold with a target GVWR, but the manufacturer doesn't know where you are going to put the cargo, more forward in the box or more aft. The axle ratings being higher allows for some cargo location variability, and also for some side to side variability.

This feeds directly into the discussion on how meaningful the published payload number is when towing with WD equipment. Tow vehicle manufacturers don't have control over whether or not an owner uses WD equipment, and without a trailer there is no opportunity to use WD equipment. With WD in use, your rated tire and axle loads represent a safe upper limit. Some will differ on that, and prefer to keep to the GVWR figure.

[jcl]

Originally Posted by GeeSag

Has anyone heard or been able to substantiate:
Manufacturers of 3/4 ton set the limit to 10,000 to avoid states where going over 10,000 changes the classification and the licensing requirements of the vehicle.
Seems 10,000 is an awfully arbitrary number.

Not just the vehicle licensing, but in some jurisdictions, also the operator licensing. Driver log books are one example.

It isn't just GVWR. In Europe, where trailer licensing gets more complicated and expensive above 3500 kg (7700 lbs) rated trailer GVW, not actual, the 3500 kg vehicle tow rating is common. There are examples of manufacturers offering higher tow ratings for those who want them, at no charge, with the only downside being licensing costs. If an operator already has to comply with those licensing regulations, there isn't a practical downside.

[jaybauman]

Originally Posted by stevegilmore

Listed on the door of my truck I have a front GAWR of #3525, and my rear GAWR is #4050. So why is my GVWR listed at #7000 and not 7575?

Unless you specify otherwise by special order, GM has done away with the 10,000 lb. GVWR limit for their 2500HD and 3500HD models since the 2020 refresh.