Question about GVWR.

[Atlee]

Why doesn't the Gross Vehicle Weight Rating equal the Gross Axle Weight Rating for the front and rear axle?

Take my F150 (heavy) pickup for example. The FGAWR = 4,050#. The RGAWR = 4,800#. Yet the GVWR = 8,200#. Why shouldn't the GVWR = 8,850#?

[ShinerBock]

TomG2 wrote:
I can read a timeline and know when I am being accused of foul play. Doesn't matter, I quit. You win. Whatever that means.

I wasn't trying to win anything. I was just debating your statement that GVWR are only set because the manufacturers knows bette and that some are set because of DOT class limitations. Then you asked for an example an I gave it. Nothing more. As far as the timeline thing, how would I know exactly what your originally stated if you changed it? If you changed it them I would have no way of knowing exactly what you said. I started my response to you and quoted your original statement. Not your edited statement.

[TomG2]

I can read a timeline and know when I am being accused of foul play. Doesn't matter, I quit. You win. Whatever that means.

[ShinerBock]

TomG2 wrote:

ShinerBock wrote:

EDIT: it looks like you changed your wording to add " for pickups like the OP's F-150" after I posted my response.

We don't even agree on when things were posted or edited. I knew that exceptions and sidetracks were being introduced and added the edit to bring it back into focus.

By the way, here is the timeline: You posted at 7:54, I replied at 8:48 and edited at 9:06, you posted the long one at 9:45. No trickery involved, just clarification of what the OP asked about. Unlike others on here, I may be wrong. Others also may be wrong but they are never in doubt.

This is what I was writing my response to which you can tell by it being the exact same in my post above.

TomG2 wrote:

I had not heard (or read) that was the way it works. References please.

I started writing my post around 9:00(which was when I quoted you) and did not finish until 9:45 because I kept getting interrupted doing other things. When I finally posted my response, I saw that you changed your post which is why I made the "EDIT". No trickery here either.

[TomG2]

ShinerBock wrote:

EDIT: it looks like you changed your wording to add " for pickups like the OP's F-150" after I posted my response.

We don't even agree on when things were posted or edited. I knew that exceptions and sidetracks were being introduced and added the edit to bring it back into focus.

By the way, here is the timeline: You posted at 7:54, I replied at 8:48 and edited at 9:06, you posted the long one at 9:45. No trickery involved, just clarification of what the OP asked about. Unlike others on here, I may be wrong. Others also may be wrong but they are never in doubt.

[ShinerBock]

TomG2 wrote:

I had not heard (or read) that was the way it works. References please.

As I stated in my post on page 2, some trucks are limited by the class they are in rather than the capabilities of the truck.

Take my 2014 Ram 2500 for example. It is in class 2B which has a minimum GVWR of 8,501 lbs and a maximum if 10,000 lbs GVWR. My truck is limited by the class it is in rather than the sum of its parts. How can I say this? Easy, take a look at the parts and their ratings in other vehicles.

My 10,000 lbs GVWR Ram 2500 with a little over 2,100 payload shares the same engine, transmission, front axle, front suspension, rear axle, tires, axle gearing, driveline, brakes, and frame as the SRW 3500 CTD 11,700 lbs GVWR that has a payload of over 3,900 lbs. How is it that my truck has the same front GAWR of 6,000 lbs as the 3500 and a rear GAWR of 6,500 lbs, which is only 500 lbs of the 7,000 lb rear GAWR of the 3500, yet my truck has almost 2,000 lbs less payload. Remember, they are identical trucks except for the rear suspension which is only rated to handle 500 lbs less by their GAWR. If you take away 500 lbs from the 3500s 11,700 lb GVWR, then that would leave you with a 11,200 lbs GVWR which would give me a payload of well over 3,000 lbs.

Lets see what that rear suspension can handle in other trucks. In the identical truck like mine, but with an almost 1,000 lbs lighter 6.4L, the truck has a 10,000 lbs GVWR with over 3,100 payload. Hmmm, seems odd. I have the same rear coils as this 6.4L in my CTD, yet it is only rated the exact weight difference of the engine. Now, before you say "the extra weight of the engine is what does it". I would like to remind you that the rest of the truck is the same as the 3500 which is rated to handle much more weight and the engine rests on the front axle system which should not affect the rear suspension at all. Besides, my truck has a 500 lbs more front GAWR than a 6.4L does.

So why does it have less payload even though the very same coils in the rear can handle more in another truck? Because my truck reaches the max GVWR of it's class long before it reaches the capabilities of its parts. If my truck had the same payload as the 6.4L version of mine, then it would give a GVWR of over 10,000 lbs which is a class 3 truck and is where the 3500 truck resides. Ram has to comply by this class rating and so does every other manufacturer. Most trucks in class 2A(which is where most "half tons" reside) are far from hitting the max of their GVWR for their class, but most trucks in the class 1 and class 2B classes are maxed out by the max GVWR of their class.


EDIT: it looks like you changed your wording to add " for pickups like the OP's F-150" after I posted my response.

[TomG2]

ShinerBock wrote:
What if a vehicles GVWR is not limited by the engineers at Ford or GM, but rather by government regulations?

I had not heard (or read) that was the way it works for pickups like the OP's F-150. References please.

[ShinerBock]

TomG2 wrote:
One can play with axle and tire rating to come up with something they "think" is better, but I let the engineers at Ford and GM do it for me.

What if a vehicles GVWR is not limited by the engineers at Ford or GM, but rather by government regulations?

[JIMNLIN]

Gr8life wrote:
Licensing requirements (taxes) are the reason for the dual GVWR ratings. Has nothing to do with GVWR or RAWR. Completely irrelevant to the discussion.

LOL....then why did you first bring the tax thing up ??? :h

Besides...... the dual GVWR on the same F350 SRW truck has all to do with the OP thread topic about GVWR.

[TomG2]

I have done the Timbren, Superspring, bigger tires, etc. etc. and never gained as much as when going from a F-150 to a F-250 or from a 1500 to a 2500. I might have gained a little stability, but really did not change the capabilities of the pickup very much. If I want a vehicle that is good for 9,000 pounds total weight, I purchase one with a gvwr of 9,000 or more. One can play with axle and tire rating to come up with something they "think" is better, but I let the engineers at Ford and GM do it for me. They "might" know a little more about the vehicles they build than I do. I still think advising anyone to exceed their gvwr is not doing them any favor, and that is what the OP asked about.

[blt2ski]

TomG2 wrote:
As others have stated, only the manufacturer knows where gvwr number comes from. Feel free to change any component you want. I hope that it is the weak link that the builder is aware of. Simply changing brakes or frame thickness may be all it takes. Good luck with your experimenting.

MDT/HDT this happens ALL the time. One could also do this very easy with a chassis cab light duty truck too. As typically the door tag is put on by the after market bed manufacture. So THEY can legally put on things like tag, drop axels and other ways and means of carrying more than the chassis came out of the factory rated too.

Light duty there is a one size fits all category mentality. When the reality is, it is way more varied than that. Along with warranty issues which I do not recall being mentioned. That is really all the manufactures door sticker gvwr is for, along with meeting certain government specs as built and finished. After that, anything goes as far as what and how you use the rig.

I've been pulled over upwards of 150% of my manufacture gvwr in rigs, so far, no overweight tickets! As I have been under my paid for license tag, along with the engineer specs of how much the road bed can handle. THIS is what the weight cops are enforcing. THere is NO enforcing of the manufactures ratings per say. If a state does less than the federal bridge law amount, that state can lose federal highway funding.

As has been noted before in these discussions. you can have an axel rated to say 30K lbs including tires springs brakes etc. ALL you will get to carry on that axel is 20K lbs, or 17500 if part of a tandem setup. It does not due one any good to have an axel rated to much more than 21K lbs in reality.

I can legally run down the road at around 20K lbs with a single wheel pickup. Not saying it is smart, safe etc. BUT if I had the correct license, I would be legal. On the other hand, I would probably still get a ticket for not meeting my states braking requrements which is for me to stop with in 25' from 20mph on a level surface. I would get red tagged, told not to drive the rig until the brakes meet spec, or off load weight so I meet spec. THIS ticket is a moving violation, it will follow me! An overweight ticket has no bearing on my insurance, driving record etc! it is a non moving violation!

My swag on the light duty trucks having axel ratings more than the gvwr is to meet certain DOT ratings specs as mentioned. Most of us in reality, can not legally per our HOA rules assuming you live in one, park your dually or single wheel rig with a manufacture gvwr of 10K or more! Which in reality, makes it a DOT class 2 or 3/4 ton truck, not a 1 ton/DOT class 3 truck. Many 35's are in reality, class 4 trucks these days too!

Enjoy the thoughts, there is no right or wrong on this, other than making sure you are under a legal wt amount, and an amount you feel safe from getting sued in a court. Then getting sued this way, the guilty line is much lower than from a legal standpoint!

Marty

[TomG2]

As others have stated, only the manufacturer knows where gvwr number comes from. Feel free to change any component you want. I hope that it is the weak link that the builder is aware of. Simply changing brakes or frame thickness may be all it takes. Good luck with your experimenting.

[Bedlam]

Your Silverado has a particular rating due to the components selected during build and the class of vehicle under which it was marketed. If you change any of those components, it is possible to decrease to increase the rating because your sticker no longer reflects the current configuration. It is also possible that your truck has derated sticker to stay within parameters that have nothing to do with safety. It's up to you, as the owner, to investigate how or why your GVWR is set if you plan modify from OEM. Just because because you deviate, does not mean you are not safe if you know the effects of your changes.

[TomG2]

The OP asked, "Take my F150 (heavy) pickup for example. The FGAWR = 4,050#. The RGAWR = 4,800#. Yet the GVWR = 8,200#. Why shouldn't the GVWR = 8,850#?"

I have driven overloaded vehicles, and it is neither fun, safe, nor wise. I don't think it is giving good advice to tell people to combine axle weights to surpass their GVWR. My Silverado clearly states, what the maximum weight of vehicle, occupants, and cargo is. Changing front tires or rear axles does not change that number.

[blt2ski]

Gr8life wrote:
Licensing requirements (taxes) are the reason for the dual GVWR ratings. Has nothing to do with GVWR or RAWR. Completely irrelevant to the discussion.

You're probably more correct in some ways than others. Others are more correct.

Yes, you could put a 8K rated dual tired axel under an S-10, Ranger or equal, Toyota used to put a dual axel under there 4banger rigs. You could maybe get the s10 recertified to show it could handle the weight. Reality is, the scale guys probably would not care, as long as your PAID for gvw was greater than the actual gvw. Along with you are under the road bed max weight limits.

As I said earlier, there is more than one way to look at this, one has to know ALL of the legal and non legal ways of looking at this issue. For me, as I stated earlier, as long as I am under the road bed limits, have a paid for license that is over what I am going down the road at. I am legal. Not necessarily "safe", but I am legal!

"Safe" certainly has many connotations too. I've driven over gvwr, gcwr with my family of 6 in a given truck or two or three. The only white knuckle issues have had to do with other issues, not weight related. Like the 35 15-20 passenger vans coming the opposite direction I was going on a 1.5 lane width mountain road. I was on the cliff side! I really do not see how gvwr/gcwr has to do with these kind of situations.

There is not right or wrong, other than to a degree, the person in the scale shack, and maybe the person doing an accident report after the fact.

Marty