Impact of aftermarket suspension and bumpers on GVWR

[Quentin]

I don't think I've seen a thread on this, but talking to a friend about trucks got me thinking. The 4Runner ranges from 6100lbs (2WD) to 6300lbs (4WD) GVWR. You can basically take the curb weight and subtract it from the GVWR to calculate payload.

2WD SR5: 1,700lbs
4WD SR5: 1,625lbs
2WD Limited: 1,575lbs
4WD Limited: 1,495lbs
4WD Trail: 1,550lbs

So, one could assume that putting a 200lbs aftermarket bumper on the nose of your truck would reduce that rating by ~130lbs, right? Now, the GVWR is largely based on the suspension and brakes. Would putting a stiffer aftermarket suspension give you more leeway to raise the numbers above (of course, assuming the brakes were up to it)? What is the criteria that the manufacturer uses to set the limit? I guess the safe bet is get a ballpark of total additional weight that your aftermarket items add and ensure that what you put in the truck doesn't exceed 6300 (4WD) or 6100 (2WD) should Johnny Lawman ever ask you to pull up on the scales.

What made me think of this was the 2011 Ford Raptor. A standard F150 Supercab is around 1,660lbs payload rating. The Raptor is 930lbs for that model year. (Fun fact, my Prius v is 915lbs, which is pretty hilarious) Basically, that baja ready suspension compromises the hell out of being able to actually use the Raptor as a truck other than carrying somewhat large, boxy items.

*note: add data pulled from cars.com

 

[homeyclaus]

There is the design GVWR, which is what you quoted.

Then there is the licensed GVWR, which is a state DMV/DOT matter. It's also the one you get a ticket for exceeding. For medium and heavy-duty vehicles you can license it for almost any weight you want, they charge by the pound. In some states and provinces inspection requirements are based on the difference between design GVWR and licensed GVWR.

 

[eddiebx]

There is the design GVWR, which is what you quoted.

Then there is the licensed GVWR, which is a state DMV/DOT matter. It's also the one you get a ticket for exceeding. For medium and heavy-duty vehicles you can license it for almost any weight you want, they charge by the pound. In some states and provinces inspection requirements are based on the difference between design GVWR and licensed GVWR.

Do you mean that some states might actually allow us to license for something higher than design GVWR? At which point, wouldn't that mean they are kind of telling you to exceed the manufacturer recommendations on payload and such? Or are we not even talking about passenger vehicles here

 

[homeyclaus]

Do you mean that some states might actually allow us to license for something higher than design GVWR? At which point, wouldn't that mean they are kind of telling you to exceed the manufacturer recommendations on payload and such? Or are we not even talking about passenger vehicles here

Most restrict that to commercial vehicles. Some define commercial vehicles as "used for business." What your business is, is your business, so they don't really ask.

And other states need a CDL, commercial plates, and a bunch of other paperwork.

And yes, one can technically overload their vehicle. In VA, MD, and DC, dump trucks with belly axles are permitted - those are pneumatic retracting axles forward of the two live axles. And these permit the trucks to carry substantially more weight, as well as weighing more. So they increase the "tare" weight as well as the licensed GVWR. I am sure Peterbilt or Mack won't honor axle or frame issues caused by the systems, the weights of those systems, or the weight the system's additional capability subsequently imposes on the vehicle.