Overweight – How Much Is Ok (not The Normal Argument)

[BillaVista]

Overweight – How much is OK (not the normal argument)

 

OK – I lied – it probably is the normal argument all over again.

 

BUT WAIT – I’d like if we could make this one a little different than the usual battle between those for and those against. You know, the kind where the heavy haulers come out swinging, the weigh Nazi’s join them in fierce battle and when the bell rings everyone retires to their corner slightly punch drunk, while nothing gets really resolved and those of us observing are left no less confused.

 

Instead, maybe we can post not only out opinions and experiences, but also what those are based on. I’d like to know about what we think the “published” limits are based on and just as importantly WHY. What the consequences are of exceeding those published limits are, for operation under which conditions (worst case?) are those limits published, what (if any) are the remedies or options one can take to mitigate the situation (of being overweight), and ultimately what people feel safe or comfortable with regarding how much overweight is OK.

 

I’ll start, and use a personal example from a decision I’m trying to make on a slide-in truck camper – let me know what you think.

 

Truck is a 2007 Chevy Silverado 2500HD 6.0 gas, CC, SB, 4x4.

 

GVWR – 9200 lbs (published)

Curb weight – 5883 lbs, full of gas (published)

Payload – 3317 lbs (published)

GAWR (f) – 4670 lbs (published)

GAWR ( r) – 6084 lbs (published) (I assume this is 2x tire limit)

Tire capacity – 3042 lbs @ 8 psi (printed on tire)

Max tow (weight carrying) – 7500 lbs (published)

Max tow (GN, 5er, WD hitch) – 9800 lbs (published)

GCWR – 16000 lbs (published)

18’ trailer – 2000 lbs (published)

Buggy, in trail trim (fuel & tools) – 4500lbs (scaled)

 

Situation: We’re looking for a truck camper to load while we tow the buggy.

 

Take the 3317 lbs payload,

- subtract 490 lbs for people (2 adults & 2 kids

- subtract 650 lbs for 10% tongue weight

 

And we’re left with 2177 lbs capacity.

 

Add, say 400 lbs for “stuff” - food, gear, camping supplies, dog, etc. and we’re down to 1777 lbs capacity.

 

Now here are the wet weights of the two campers we looked at (includes full water and propane), and how much each would put me over-weight.

 

Lance 861 – 3535 lbs – over by 1758 lbs

Lance 845 – 2703 lbs – over by 926 lbs

 

That’s seems quite a bit – which leads to my question about how much over is ok (if any?)

 

Here are my thoughts:

 

Why it might be OK to be over:

- first, anecdotal evidence seems to indicate that maybe 80% of haulers out there are over by some amount,.

- One argument might also be that the factory “published limits” are conservative. Why would this be so? Liability and warranty spring to mind, combined with the conditions under which the published limits apply. I.e. – presumably if my published payload is 3317 lbs, I can load the truck with that, all day, every day, in extreme conditions (up and down hills? temperature extremes?) for the reasonable life of the truck – presumably for at least as long as the warranty (7 years, 150,000 km). And presumably this is also for driving at min posted speed limits in traffic.

 

So how would these “published limits” change for occasional use (6 x year for a few days at a time) at slow speed, on flat ground, in low-traffic areas, and with the truck brand new, not beat on and worn down?

 

Why it might not be OK to be over:

Then again – the truck market is popular and very competitive – manufacturers are using towing and hauling capacities in major advertising – so presumably they squeeze every pound out of their limits as they can – to “beat” the competition. But then agin – who has the final say – the engineer? The bean counter? The lawyers?

 

OK, to get to the tech of this – what are the limiting factors and effects of exceeding, and what if anything, can be done to mitigate.

 

My guesses are:

 

- number one is probably braking / stopping distance. I assume the lawyers are going to make them limit the capacities to where the average guy can stop reasonably in traffic?

- Possibly tied for number one would be tire limits – especially after the Ford/Firestone fiasco. It’s no coincidence that my tires are rated to 3042 lbs each and the RAWR is 6084 lbs. I don’t think you’d ever want to exceed the tire’s limits, but you can get higher rated tires (3400 lbs are common), and of course you’d have to scale the rear of the truck to do the calcs. Anyone know what percentage of the trucks curb weight is on the rear axle stock, empty?

- Next I’m not sure, maybe springs / suspension (could be helped with air bags, shocks, overload leafs); or it might be cooling / tranny. Careful “grandpa driving”, aftermarket coolers / rads might be able to help with this a bit. I’d also hate to think that a brand new $50,000 truck fully loaded is within 1000 lbs of major engine or tranny failure – but maybe I’m being naive?

 

What’s next? Anything else? I’ve left out power because people were carrying and hauling big loads well before any stock truck came with 300hp.

 

Lastly – driving style has to be a factor. I know there’s a whole crowd who must be able to tow/haul at 80mph and zip in and out of traffic while doing it – you know the one’s that no matter what you have they say you “should’ve gotten bigger/more” It seems they think you need a 1-ton diesel dually to hauls a snowmobile.

 

But that’s defiantly not me – I just retired my 78 that maybe made 140hp on it’s best day, and that day passed 15 or 20 years ago!! AND it had lousy drum brakes and a weak vaccum booster. The new hydro-boost 4-wheel discs are worlds apart.

 

But now I’m rambling.

 

What are your thoughts/experiences?

[ZZ327]

you are waaayyy overthinking this

 

 

as long as what you plan to carry and haul at the same time doesnt extremely exceed your GCWR at 16000lbs you will be fine. You basically have a 1 ton pickup, It will handle alot. Its already set up with Heavy duty supension, transmission, Trans Cooler,trailer brake controller.

 

our 02 2500hd ECSB 4wd my dad uses for work has a 8 ton rating on the plates. They run about 80 psi in the tires. Im sure ive personally overloaded it a time or 2! Its common sense, when loaded like you plan. Dont speed in heavy traffic, take extra space for slowing down and braking(look at getting trailer brakes if you dont have them).

[Burbman]

Billa Vista,

 

All good questions, and have seen similar posted on the RV forum, but no concrete answers. GVWR is set by some combination of mechanical limits, marketing spin, and legal CYA, but the exact method for arriving at GVWR is kept bhind closed doors at GM. It's no secret that the truck will handle more than the GVWR, but with some sacrifice of safety magin and reliability. How much ia anybody's guess. Sadly, you'll see responses like the one above from guys that have no idea of what GVWR even means. To suugest the the can can haul the full 16,000 GCWR in the truck is ridiculous, whether is has 8-ton plates or not.

 

I would personally not buy either of those Lance campers for your 2500HD. I think 900+ lbs is a lot to be overweight especially for extended periods. Also, truck campers sit high in the bed, and most guys prefer duallies because they add additional lateral stability.

 

Going that much overweight is like Russian roulette....you won't know what the limiting factor is/was until it happens. Could be unable to stop, fried rear axle and/or trans, rollover crash, etc. Now I don't consider myself a badge-carrying member of the weight police, but common sense needed too. I've taken at one 1000 mile camping trip that I know of where my Sub weighed in at 8900 lbs, 300 lbs over the 8600 GVWR. Of course the GCW was 17,400 lbs, well under the 19,000 GCWR. Nothing broke, blew up or overheated on that trip but I'm not looking to do it agin. [Wound up with 2 extra kids when buddy's Expedition toasted it's tranny leaving him and his DW stranded in NJ. At least the kids got to go on vacation.]

 

To answer your question, is the truck going to fall apart day #1? No. I would go to 265's in E rating and increase your capacity there to 3415 each at 80 psi. Would I do it? No.

[kaneak2002]

BillaVista,

 

I myself have wondered the same thing. I've got a 05 2500HD, in the glove box there is a label for slide in camper capacities, mine says 2322lbs is max. I see your payload is 3317lbs, do you know if they have changed the rating? I havn't scaled mine yet but I have a 8.5 ft Alpenlite that weights in at 2302 (label weight) thats with 30 gal. water and 5 gal propane.I put air bags on mine, I realize that don't increase my GVWR but it sure stabelizes the load. I really need to scale mine empty and fully loaded to see exactly where I'm at. (Good post I hope you get some facts related to this subject!)

[s-ten]

What we have is a Lance that weighs in around 3500 lbs and we haul it with a 3500 dually with no problems. We have friends that have your exact truck that are running about 3100 lb Lances and tow fishing boats behind. All of the people that have the 2500HD trucks put airbags in them and they haul the campers just fine. The campers can be hauled without airbags but they are relatively unstable.

 

If I was you I would put airbags on whatever you decide, they really help to stabilize the trucks.

 

Hope this helps

[99silverado1500]

I know Im going to stir something up here, but on any chevy, I wouldnt exceed the ratings AT ALL. Their ratings are way over rated, and there is no way I would load more then specified ESPECIALLY if its in warranty. I know my truck, ive had leaf springs replaced many times, and I have the stock number of leafs, and they are a tad stronger then stock, and they bounce off the bump stops over every single decent bump in the road, and every speedbump I go over, they are bouncing off the stops too WHEN ITS EMPTY!!!! Loaded, thats another story...dont even get me started. Shocks were also replaced and springs are fine. My old ford I could exceed the load rating and the truck would even out. Mine I load 1000 lbs less, and its dragging on the ground basically. The fords seem to lack reliablity, especially in the diesels, thats why Im a semi proud chevy owner now, but still I would never exceed any chevy/gm rating.

[Genuinefine409]

I know Im going to stir something up here, but on any chevy, I wouldnt exceed the ratings AT ALL. Their ratings are way over rated, and there is no way I would load more then specified ESPECIALLY if its in warranty. I know my truck, ive had leaf springs replaced many times, and I have the stock number of leafs, and they are a tad stronger then stock, and they bounce off the bump stops over every single decent bump in the road, and every speedbump I go over, they are bouncing off the stops too WHEN ITS EMPTY!!!! Loaded, thats another story...dont even get me started. Shocks were also replaced and springs are fine. My old ford I could exceed the load rating and the truck would even out. Mine I load 1000 lbs less, and its dragging on the ground basically. The fords seem to lack reliablity, especially in the diesels, thats why Im a semi proud chevy owner now, but still I would never exceed any chevy/gm rating.

 

 

Sounds like you have some major problems if your hitting bump stops when your empty, or else you weigh a ton and a half. Does your truck have a load spring? i had a 1996 Z71 i put a 2200lb skid in the back of which is way over the limit and i was like 5 inches away from bump stops. I've had this truck for years and it had 184,000 on it and i never replaced the leaf springs. If you use common sense you can can go over the weight limit. In PA you are allowed to register you truck up to the highest weight in its weight class. example is my 2500HD has a GVWR of 9200lbs. this is a weight class 4A. the 4A weight class goes from 9,001 to 10,000lbs. So on my registration I can legally register the truck at 10,000lbs which is 800 over mfg rating but legal and people do it all the time here. on some trucks you can go even more over than that depending on where it falls in the class. some people can say never go over wieght limit, others will say you can. I say you can to an extent, just be smart about it and drive safe and don't forget the more your truck weighs, they more damage it is capable of doing.

[GetMore]

Something else to look for is the rear AXLE rating. I'm not sure where to find it, but I have seen that info before. What the truck is rated for at the axles, and what the axles are rated for are two different things. Upgrading tires could increase the truck's rating, but eventually you will near the axle's limit.

 

I don't think you are going to hit the limit with your setup.

 

Something else to look into is what the actual axle weights are going to be. With passengers you will be adding weight to the front, but everything else will be on the rear.

[Ag Teacher]

Air your tires up to the max and don't exceed the tire ratings and you'll be okay.

 

GVWR is what the government uses to decide if the manufacturer has to meet fuel economy standards or not. It's also used to decide what your insurance cost. Unless your hauling comercially, it shouldn't matter much to you.

 

Stay off of scales and load your truck. It's tougher than most will give it credit for.