Weight concerns.

[Fireeater661]

I have a 2018 ram 1500 eco diesel my tow capacity is around 9200 and I’m thinking about buying a pull behind camper that has a dry weight of 7728. My question is how much room should I leave between my full capacity and my camper weight

 

[MADDOG]

I'd suggest you do some trailer math before you commit to a trailer.

You need to know your truck's GVWR, the weight of passengers fuel & gear in the truck, the trailer's GVWR and UVW (unloaded vehicle weight - the difference between those is your max cargo weight), the weight of what you will be loading into the trailer and the trailer's tongue weight when loaded.

You'll need to plug in those numbers, plus some others, into a towing calculator spreadsheet.

There is a good one I've used a lot that can be downloaded at the link below.

Tow Capacity Worksheet

 

[nlambert182]

Those are the wrong 2 numbers right off the bat.... tow capacity of the truck when talking about a camper doesn't matter. That's based upon a 10% tongue weight on a flatbed trailer where the weight can be moved around to lighten the tongue. Camper weight is static. Dry weight of a camper is also irrelevant. It only weighs that when it leaves the line. Both are 2 numbers that you will never see in real life when talking about RVs.

MADDOG posted a good link.

If you want the quick method to give you a general idea (you can do this with your phone calc while on the lot looking):




Take the payload number that's on the sticker on the door of the truck. Subtract the weight of all cargo, people, and anything the truck didn't leave the assembly line with from that number. THAT is your available remaining payload.



Take the GVWR of the trailer and multiply x 15%. That is the anticipated worst case scenario tongue weight of the trailer. Subtract the tongue weight from the remaining truck payload. If you're over, pick again.


You will never go wrong with that simple formula.

 

[Tulecreeper]

When calculating the weight of a trailer, always assume is will be at max GVWR all the time. Let's assume your cargo carrying capacity (CCC) is 1500#. So, in your case it would be 7728# + 1500# = 9228#. That is 28# over your max towing capacity.

Now, as a safety rule of thumb I always try to not tow more than 80% of my max tow cap. In my case, my max tow cap is 15,500# so I will try not to tow more than ~12,000#. But that's just me. If you went by the same rule of thumb you would be at 80% capacity at ~7400#.

 

[HEMIMANN]

Yep - many towers use 80% of published maximums as real maximums. Published maximums are usually idealized and unrealistic values, just like most of the rest of the Marketing, er, Owner's Manual.

 

[Burla]

Tow Ratings are set to protect your truck by the manu, so if you are on the upper end of it just learn how to drive heavy. The real issue is tongue weight, past that you are mostly covered and then some with your hitch staying on the truck. Get a class 5 hitch and keep tongue weight in spec, your good with those numbers.

 

[dhay13]

I'd be more concerned with your GRAWR. At about 1000-1100lbs tongue weight you will likely be very close to maxing out your rear axle weights

 

[nlambert182]

What almost everyone who doesn't tow rv's tends to forget is static weight vs. adjustable weight. More than 80% of the weight on a camper can't be adjusted. Cabinets, appliances, wall framing, ACs, etc... can't be moved to lighten the tongue weight. Couple that with furniture and that most travel trailer storage is in the nose and you quickly learn that tow ratings are all but useless to go by. There's just no way to adjust enough weight to lighten the tongue enough to ever reach the max tow rating of the truck. People will try and then end up with a super light tongue and a squirrely trailer. Then there's frontal area. You're towing a giant box that is far from aerodynamic in most cases. All of those things combined mean that you typically need to be well below your tow rating to tow a specific camper. It's easy math... but it's different. You can fudge the payload number and sometimes slightly exceed it if you just have to.. but don't exceed the RAWR. I too fall into the category of towing at around 80%. I never max out my capacities and knock on wood, never had a problem either.

What chaps my rear end the most are RV salespeople. They always advertise dry weights. The problem is that dry weight is out the window the second it pulls onto the dealer lot and they install propane tanks and batteries. Then any addons they install. They never mention GVWR. Often times they're a few hundred lbs heavier before anyone buys them. Toss in their stuff and it is a LOT heavier than they thought. Folks will use those dry weights as gospel.

I got into an argument with a salesperson at our last RV show. We were looking at the Riverstone 419RD as a potential for when we relocate to Florida full-time. They were advertising that it only weighed 19,000 lbs but only had a pin weight of 2,800 lbs and could be towed by some 2500s. Big sign that advertised this. I took him around to the GVWR sticker. The GVWR on that trailer is 23,950 lbs and the realistic pin weight would be closer to 5,300 lbs. Certainly not a trailer that ANY 2500 could tow in the numbers, and even some 3500s would be ruled out. He said they don't go by GVWR. No kidding....

 

[HEMIMANN]

What almost everyone who doesn't tow rv's tends to forget is static weight vs. adjustable weight. More than 80% of the weight on a camper can't be adjusted. Cabinets, appliances, wall framing, ACs, etc... can't be moved to lighten the tongue weight. Couple that with furniture and that most travel trailer storage is in the nose and you quickly learn that tow ratings are all but useless to go by. There's just no way to adjust enough weight to lighten the tongue enough to ever reach the max tow rating of the truck. People will try and then end up with a super light tongue and a squirrely trailer. Then there's frontal area. You're towing a giant box that is far from aerodynamic in most cases. All of those things combined mean that you typically need to be well below your tow rating to tow a specific camper. It's easy math... but it's different. You can fudge the payload number and sometimes slightly exceed it if you just have to.. but don't exceed the RAWR. I too fall into the category of towing at around 80%. I never max out my capacities and knock on wood, never had a problem either.

What chaps my rear end the most are RV salespeople. They always advertise dry weights. The problem is that dry weight is out the window the second it pulls onto the dealer lot and they install propane tanks and batteries. Then any addons they install. They never mention GVWR. Often times they're a few hundred lbs heavier before anyone buys them. Toss in their stuff and it is a LOT heavier than they thought. Folks will use those dry weights as gospel.

I got into an argument with a salesperson at our last RV show. We were looking at the Riverstone 419RD as a potential for when we relocate to Florida full-time. They were advertising that it only weighed 19,000 lbs but only had a pin weight of 2,800 lbs and could be towed by some 2500s. Big sign that advertised this. I took him around to the GVWR sticker. The GVWR on that trailer is 23,950 lbs and the realistic pin weight would be closer to 5,300 lbs. Certainly not a trailer that ANY 2500 could tow in the numbers, and even some 3500s would be ruled out. He said they don't go by GVWR. No kidding....

Add fresh water and propane weight, plus all your junk in the storage compartments.

 

[Panduh]

Don't forget to add in the weight of your hitch. A typical WDH, which you probably need, is over 100 lbs.
The most accurate way to make sure you're within your payload, your rear axle max weight and your tongue weight, is to take the fully loaded rig (including passengers and bed luggage) to CAT scales.

 

[Bramic71]

In my opinion, you should not tow more than 6900# or 75% of your tow rating behind your truck. Personally I believe you would be too heavy to safely and comfortably tow that camper even towing at the dry weight before propane batteries,water,personal belongings, etc. are added to the camper. Just my personal opinion and we tow a camper often. Good luck on your research and absolutely do not listen to what an rv dealer tells you about what you can tow.

 

[RamRigger]

Adding into this aluminum vs steel receivers. I need to check the tongue and towing weight on it mine again, its been awhile, but I bought it because at the time it was more than adequate to haul my 18' Duckworth with the added motors and batteries, seats, down riggers etc. But how does anyone feel when comparing overall strength between aluminum vs steel receivers?

 

[Bramic71]

Steel i believe would definitely be better for hauling heavy and would have less wear and tear over time. Although if not hauling heavy the aluminum would be lighter and do better in some corrosive conditions. That would be my opinion on the matter.

 

[HEMIMANN]

Adding into this aluminum vs steel receivers. I need to check the tongue and towing weight on it mine again, its been awhile, but I bought it because at the time it was more than adequate to haul my 18' Duckworth with the added motors and batteries, seats, down riggers etc. But how does anyone feel when comparing overall strength between aluminum vs steel receivers?

I doubt if they make large receivers in aluminum. Yes, you can design in the same strength as steel, BUT aluminum deflects 3x as much as steel! Where stiffness is important, you go with steel.

Which is why aluminum engine blocks and heads are so heavily ribbed - to build in stiffness with geometric shapes that the raw material does not have (I used to do this).

Watch an airliner wing flap in turbulence. I like to tease people about it when flying (wow! look at the wing flap!!!) You don't want your trailer tongue bouncing up and down the road, likely hitting pavement on harsh bumps if aluminum.

 

[nlambert182]

WeighSafe, Bulletproof, and B&W all make aluminum receiver hitches to fit up to a 3" receiver and are rated for up to 21k lbs. A little flex on a receiver hitch can be a good thing to help absorb some of the impact of the road and prevent it from transferring through the RV frame. Planes are a little different animal. The wings are designed to flex to absorb stress. The entire inner skeleton of the stub wing on a Blackhawk is a piece of billet aluminum and it holds a ton of weight and has to withstand a lot of force. I used to make them.

Nothing wrong with aluminum if it's used properly. I presume that the reason the ribbing is added in engine blocks is to help maintain rigidity due to heat cycling and the massive pressure inside the block during firing. Hitches and airplane wings aren't exposed to those sorts of stresses. I don't build engines though, so I could be wrong on that front.

 

[HEMIMANN]

WeighSafe, Bulletproof, and B&W all make aluminum receiver hitches to fit up to a 3" receiver and are rated for up to 21k lbs. A little flex on a receiver hitch can be a good thing to help absorb some of the impact of the road and prevent it from transferring through the RV frame. Planes are a little different animal. The wings are designed to flex to absorb stress. The entire inner skeleton of the stub wing on a Blackhawk is a piece of billet aluminum and it holds a ton of weight and has to withstand a lot of force. I used to make them.

Nothing wrong with aluminum if it's used properly. I presume that the reason the ribbing is added in engine blocks is to help maintain rigidity due to heat cycling and the massive pressure inside the block during firing. Hitches and airplane wings aren't exposed to those sorts of stresses. I don't build engines though, so I could be wrong on that front.

Flexing does not absorb stress, unless you get into fracture mechanics (strain energy). Strain (flexing) is a property of a material, that is all. Aluminum strain per unit load is 3 times that of steel. The ribbing and geometry in aluminum stressed parts is designed to accommodate the 300% higher strain. Obviously, engine blocks would fail if allowed to wobble that much, therefore the thickness and ribbing is designed in greater than that for iron blocks so that bearings won't fail. FEA has allowed the use of aluminum where previously it was not. We used the ANSYS program.

 

[RamRigger]

All good replies. I just didn't make it out today because of the heat. I'll try to do that tomorrow and report back on receiver ratings

 

[nlambert182]

Flexing does not absorb stress, unless you get into fracture mechanics (strain energy). Strain (flexing) is a property of a material, that is all. Aluminum strain per unit load is 3 times that of steel. The ribbing and geometry in aluminum stressed parts is designed to accommodate the 300% higher strain. Obviously, engine blocks would fail if allowed to wobble that much, therefore the thickness and ribbing is designed in greater than that for iron blocks so that bearings won't fail. FEA has allowed the use of aluminum where previously it was not. We used the ANSYS program.

Fair points.

I wouldn't hesitate to get a well-built aluminum receiver hitch though. The B&W and weigh safes have been around a long time. I don't know that I've ever heard of (or seen) one fail.

 

[RamRigger]

Went out to look at the hitch mount and nothing I could see was stamped into it so I went to their website (below).My aluminum hitch mount receiver is rated as follows:

• 5000 lbs 1-7/8″ Capacity GTWR
• 7,500 lbs 2″ Capacity GTWR (which is the ball I use)
• 12,000 lbs 2 5/16" Capacity GTWR

I use a 2" so I'm good with our right at 3,000 lbs boat and gear

Here's the website: https://alumatow.com/aluminum-adjustable-interchangeable-hitch-mount-6-drop-2/
Here's the hitch receiver: https://alumatow.com/aluminum-adjustable-interchangeable-hitch-mount-6-drop-2/

I have emailed them to verify that 12k (1200 lb tongue weight) for our Ram 2500 Big Horn crew cab, 6'4" box, 4x4, rated at 15,700 lbs maximum trailer weight rating, a payload of 2050 lbs, and a GCVWR (gross combined weight rating) of 25,265 lbs. But in the specs I can't find anything for the hitch that's factory installed, so I went to: https://www.ramtrucks.com/content/d...hure/my24_Ram_HD_Customer_TowPayChart_3.2.pdf and see a couple of different ratings of 14,900 and 19,980 for a 10,000 lbs GVWR rating.

Scrolling down to Maximum Payload, to me means what the frame design will hold, but not the hitch with a rating of 2760/2500

Has anyone a way to get this info directly from Stellantis?

 

[lpennock]

My understanding is the 10K rating is the bolt on 2" receiver the 14.9k is for the factory installed 2" receiver and the 19.9K is for the 2.5" receiver.