WD Receiver Numbers Confusion

[Danno59]

Originally Posted by NH_Bulldog

Understand that you want a 10-15% safety factor. With your numbers you have a 3% safety margin. Too close for my liking. What kind of tires on your tow vehicle? Easy way to tell is look at max inflation pressure; 44 psi? You have a passenger car tire, too dangerous to tow your trailer. 51 psi? A little better, but not great and you would have to run at max pressure to tow. 80 psi? That is a light truck (LT) tire, LRE (load range E) and is the tire you need.

Then you have to know that manufacturers rate a vehicle’s trailer towing capacity with a flatbed trailer loaded with steel weights. Unrealistic and largely irrelevant in this situation.

As you mentioned, you do need to think about frontal area and side area of the trailer. Frontal area affects wind resistance and adds theoretical weight to the set-up. Most manufacturers publish a towing guide that provides details specific to your vehicle. Side area is a factor depending on your tow vehicle’s wheelbase. The shorter the wheelbase, the more the trailer will “wag the dog”. The key numbers for wheelbase are: The first 110 inches of wheelbase allow for a 20-foot trailer. For each additional four inches of wheelbase length, you get one foot more in trailer length. That means your tow vehicle needs a minimum wheelbase of 130 inches for your trailer (the box is 22’ plus 3’ for the tongue = 25’).

No one here is judging, just trying to educate. For what it’s worth, many if not most of us have learned this from firsthand experience and we are just trying to save you from a mistake that could cost you or someone you love or even some innocent driver on the road from an unnecessary injury or loss of life.

51 psi tires are currently on my TV. I have plans to upgrade to LRE before my next tow.

My TV has 144.5" WB, with 3.73LS rearend, so that's helpful.

Safety factor %. What is the reason for the safety factor? Where did this idea come from? Does it have to do with the physical dimensions of the TT? For instance, one might be loaded to max on a TT that is 9' tall and 19' long, but might give a safety factor of 10%-15% for a TT that is 11' tall and 26' long?

Thanks

[Roscommon48]

Lots of input but I'd say this is an insurance claim

[JRTJH]

Originally Posted by Danno59

Thanks for the info. Curious what this weigh is for? Thanks

The first weight gives you the "weight distributed" values. That's the weight on the axles "as it's transferred using the spring tension bars"...

The second weight, with the spring tension bars disconnected, gives you the "actual weight on each axle". With those two numbers (and the actual weight of the truck without the trailer) you can calculate the true tongue weight of the trailer. If you only have the first weight, you can not calculate the true "static weight" of the trailer tongue (only the "weight transferred tongue weight will be available). Both weights are necessary to get the "full data set"...

[Danno59]

Originally Posted by travelin texans

RV dry weights & truck max tow weights mean ABSOLUTELY NOTHING when trying to match RVs to tow vehicles.

Is that more because of the height, width and length of an RV? As opposed to say, a flatbed trailer or a dump trailer?

[LHaven]

Originally Posted by Danno59

Is that more because of the height, width and length of an RV? As opposed to say, a flatbed trailer or a dump trailer?

It's because the RV dry weight is a stripped weight without propane tanks, battery, fluids, hitch, possibly the spare, and other things you absolutely cannot tiw without… and because the horizontal tow figure is not the truck limitation you exhaust first -- that's the payload capacity of the truck, which has to accommodate your passengers, gear, and trailer tongue weight.

[sfem192]

Am I missing something here? The original post stated he was using a 5000 lb receiver with a 9000 lb WDH. Isn’t the weak link here the receiver? He should upgrade the receiver to handle the weight of what is being towed.

[NH_Bulldog]

Originally Posted by sfem192

Am I missing something here? The original post stated he was using a 5000 lb receiver with a 9000 lb WDH. Isn’t the weak link here the receiver? He should upgrade the receiver to handle the weight of what is being towed.

Remember that hitches and receivers both have two different ratings, one for weight carrying and one for weight distribution. Typically you might see Weight carrying capacity of 500 lb tongue/5,000 lb trailer, and weight distribution capacity of 1,000 lb tongue/10,000 lb trailer.

[Harried Harry]

Great points made by everyone. I'm one who has been looking at the upgrade part, but I want/need a bigger, HD truck. My current truck (08 Dodge 2500) is fine with my 03 Cougar but not with my Lance 915 truck camper (I'm right at the edge). Everything tows fine or hauls fine, but I'm not getting any younger and I love to travel up to Colorado into the high country.

I started out tent camping, then used a pop-up, then the 5er, then a small truck camper, then a large one (too large for my truck), then to a smaller unit. Now my body tells me No More tent camping! since the last time it took 15 minutes to get out of the sleeping bag. Lesson learned.
If you can afford to upgrade the truck to a larger one, do so to begin with so you won't need to do so again in ten years. My truck is paid for but is 12 years old. I would like something which both my wife and I can drive without any issues. The new ones have a lot of sensors to tell us if we are starting to go off the road, so I want these safety items.

[blubuckaroo]

We've just recently gone through learning the geometry of the load leveling hitch.
We've been using our 15' single axle for years, and there's something to be said for the simplicity of a drawbar hitch. Sure, tongue weight is still your friend, but then again it's just a 15' trailer. BTW, we still use the little trailer. Many small campgrounds won't allow even medium size trailers. Our 1971 Excel is the trailer in my avitar.

Now we've got 550-600 pounds of tongue weight. Way more than you would want to carry on the back of your truck. That's where the distribution hitch comes in. It applies some of that load to the front wheels too, keeping the tow vehicle level and more weight on the front for better handling.

We recently switched tow vehicles. The new truck has a hitch height that is 2" lower than the old truck. In this case, there's more involved than adjusting chain links on the distribution hitch. The angle of the weight distribution head as well as the height need to be changed. Those bolts are big and the recommended torque on them was around 300 foot pounds. I wasn't equipped for that, so I took it to the RV shop ton have the hitch set up. $60 well spent. I see rigs being towed quite a bit with improperly set up weight distribution hitches. When the geometry is right, towing is a much more pleasurable experience.

[Fourbtgait]

Originally Posted by chuckster57

Let me reiterate what's been said before and in this thread, DO NOT USE EMPTY (dry) weights.

When calculating always use the GVWR or ACTUAL WIEGHT. We all say we aren't going to travel with much stuff or any water..I have learned that there will come the day that you find yourself hauling all the waste water somewhere to dump. At that point your most likely way over the limits. I have had to haul a full gray and black tank from Nebraska to South Dakota because where I stayed didn't allow me to dump even the gray. Then theres the gear that seems to always grow into "we need that too".

No one is trying to judge you, and in the end its totally your choice. most of us have been there done that and just trying to help you not make the same mistakes we have.

Depends on the trailer.
Mine loaded to leave for trip is 750 TW because of freshwater tank location in front of axle. Even if I can’t dump black/greywater, my TW drops to 600 pounds because it is behind the axles and the fresh water has been depleted, so I move loose items to the front pass through to counter balance the weight shift.

I balance typically from 11% Tw to 13%. I have never had an issue of even from 10-12% TW. It is a balancing act.

[blubuckaroo]

Originally Posted by Fourbtgait

Depends on the trailer.
Mine loaded to leave for trip is 750 TW because of freshwater tank location in front of axle. Even if I can’t dump black/greywater, my TW drops to 600 pounds because it is behind the axles and the fresh water has been depleted, so I move loose items to the front pass through to counter balance the weight shift.

I balance typically from 11% Tw to 13%. I have never had an issue of even from 10-12% TW. It is a balancing act.

You're right about that. Tongue weight can vary quite a bit depending on how it's loaded.
I've always felt that tongue weight is my friend. More is a good thing.

[flybouy]

Originally Posted by Danno59

51 psi tires are currently on my TV. I have plans to upgrade to LRE before my next tow.

My TV has 144.5" WB, with 3.73LS rearend, so that's helpful.

Safety factor %. What is the reason for the safety factor? Where did this idea come from? Does it have to do with the physical dimensions of the TT? For instance, one might be loaded to max on a TT that is 9' tall and 19' long, but might give a safety factor of 10%-15% for a TT that is 11' tall and 26' long?

Thanks

Safety factor is just that, a factor or margin of safety. Because it has a listed max weight that doesn't mean you should be using that max weight at all times OR in all conditions. All roads have a max speed limit. Typically, when you approach a curve, or other road condition you will see a sign posted with a reduced speed according to the condition. What you will not see, is a change in those signs if it's raining or snowing or foggy. Common sense would dictate that you decrease your speed and distance between traffic to increase the margin of safety.

Your truck may have a tachometer red line on it. That is the LIMITS on engine speed. Run the engine at that red line all the time and I guarantee you will greatly reduce the life of the engine. Common sense should tell you not to redline the engine for any length of time. IMHO, common sense should also be used in loading the trailer to give a "margine of safety".

[Fourbtgait]

I also run test weights various scenarios so have a decent idea of TW all the time.
Below is current trailer
We also clean trailer out each trip, don’t accumulate needless junk.

Trailer Test Weights
Sticker empty- 4350
Sticker gross-6500

11-9-19 average tongue weight minimum gear, no water- 591 pounds

4-12- 20 average tongue weight full camping load set up from list. no water. 625 pounds.

4-12-20Remove ice chest, fridge and cabinet food of 150, no water. 700 lbs

4-12-2020 average tongue weight camping load from list, full of water per set up below- 750 pounds.

4-12-2020 average tongue weight camping load from list minus food/beverages, waste tanks 1/2 full as if leaving camp. With part water- 675 tongue weight

4-12-2020 average tongue weight as above but waste tanks 1/2 full, no water left- 600 pounds tongue weight

Test weighing set up:
5 gallons drinking water in bath- 45 lbs
stuff in rear compartment- 20 lbs
White ice chest beverages- 50 lbs
Fishing gear, solar panel, carpet, wheel chocks, etc front compartment
Clothes at bed- 25 lbs each side
Food in refrigerator- 50 lbs
Food in cupboards- 50 lbs
Misc in slide- 10 lbs


4-18-20. Water, no added gear. 725 pounds tongue weight
100 pounds added to nose compartment gives just under 800 pound tongue weight to set up hitch