Towing capacity??

[ROBERT CROSS]

......snip "I think the differences in receiver classes, although imprecise due to a lack of standards, are at least directionally clear and agreed."

Facts...get them straight.

I will accept your opinions as opinions realizing that SAE may not apply in the GWN.

Bob
🇺🇸

[Gene]

I'm having trouble following the receiver weight posts, but I think understanding how the WD hitch works may help someone. The hitch adds rigidity to the trailer—tow vehicle combination. Rigidity is created by either bars or chains and bars. As force is projected forward, the truck (or SUV) front end is forced downward by picking up some of the transferred weight, hopefully leveling the truck. Thus weight is transferred, but it always will show up somewhere—the truck axles. I have no idea how to caculate how much weight is transferred to each truck axle. I only was an engineering major for two months until I saw how it was interferring with beer and girls study (or as a politician would say, "youthful indiscretions").

Think of the trailer and TV combination as one vehicle with three or four axles connected by a pivoting center point—the hitch assembly. That makes it easier to see how weight is distributed among all the axles.

In calculating cargo or payload, add in the hitch assembly weight—or two thirds of it—to the truck. I think most hitch (head, bars, chains, ball) probably are around 50-55 lbs. I forgot that in my last post.

[jcl]

Originally Posted by ROBERT CROSS

......snip "I think the differences in receiver classes, although imprecise due to a lack of standards, are at least directionally clear and agreed."

Facts...get them straight.

I will accept your opinions as opinions realizing that SAE may not apply in the GWN.

Bob

Actually, we commonly use SAE standards in the Great White North, as our automotive industries are tightly integrated with yours. Some of us can even show SAE membership cards, although I have let mine expire. I am familiar with the SAE receiver standard. It isn't very precise, nor is it enforced. That is why you can see hitches rated 3500 lbs marketed as Class III, when Class II covers up to 3500 lbs, and Class III covers up to 6000 lbs. There are hitch manufacturers selling 3500 lb Class III hitches. Those simply looking for a Class III and thinking that will address the requirement need to wary of this. Saying that the SAE standard covers it would be like saying that the designations 1/2 ton and 3/4 ton define capacity. There may be a general trend line, but it isn't a spec. You need to read the label, not the advertising copy.

There are hitches rated above 6000 lbs that are marketed as Class III, when that category should be Class IV. But it really gets imprecise when you get to class V. SAE doesn't recognize Class V, or at least they didn't the last time I read the standard. They don't cover above 10,000 lbs, which is the limit for the Class IV standard. So when you asked "what is the difference between Class II and Class V?", one of the differences is that the former may be tested to the SAE standard you linked, while the latter is non-conforming and simply the product of marketing. It gets really hazy when a hitch seller says that they have tested their "Class V" hitch to the SAE standard. How is that even possible?

I stand by my opinion that this is all very imprecise, while agreeing that directionally, higher class hitches tend to have higher ratings.

None of this addresses the original point, which was that a tow rating specified by a manufacturer and which requires the use of WD equipment, isn't about the receiver as you stated. WD equipment doesn't reduce tongue weight where applied, and it doesn't put less stress on the receiver (it adds a bending moment), so it is illogical to say that adding WD equipment and thus raising the rating is due to the receiver. What is left is that it must be due to the effects of using WD equipment. And that challenges your opinion that if you need WD equipment you need a heavier vehicle. Manufacturers who design and build vehicles disagree with you. WD equipment is a feature designed to increase performance, it isn't just a "nice to have" like heated seats.

[jcl]

Originally Posted by Gene

I'm having trouble following the receiver weight posts, but I think understanding how the WD hitch works may help someone....

Weight isn't just transferred to the TV front axle, and off the TV rear axle, it is also transferred to the trailer axle(s).

Add in the weight of the WD equipment to total weight, but also consider that the measured tongue weight will change because you are measuring it in a different location from the trailer axle centreline, since WD equipment adds length here.

[ROBERT CROSS]

Originally Posted by jcl

Actually, we commonly use SAE standards in the Great White North, as our automotive industries are tightly integrated with yours. Some of us can even show SAE membership cards, although I have let mine expire. I am familiar with the SAE receiver standard. It isn't very precise, nor is it enforced. That is why you can see hitches rated 3500 lbs marketed as Class III, when Class II covers up to 3500 lbs, and Class III covers up to 6000 lbs. There are hitch manufacturers selling 3500 lb Class III hitches. Those simply looking for a Class III and thinking that will address the requirement need to wary of this. Saying that the SAE standard covers it would be like saying that the designations 1/2 ton and 3/4 ton define capacity. There may be a general trend line, but it isn't a spec. You need to read the label, not the advertising copy.

There are hitches rated above 6000 lbs that are marketed as Class III, when that category should be Class IV. But it really gets imprecise when you get to class V. SAE doesn't recognize Class V, or at least they didn't the last time I read the standard. They don't cover above 10,000 lbs, which is the limit for the Class IV standard. So when you asked "what is the difference between Class II and Class V?", one of the differences is that the former may be tested to the SAE standard you linked, while the latter is non-conforming and simply the product of marketing. It gets really hazy when a hitch seller says that they have tested their "Class V" hitch to the SAE standard. How is that even possible?

I stand by my opinion that this is all very imprecise, while agreeing that directionally, higher class hitches tend to have higher ratings.

None of this addresses the original point, which was that a tow rating specified by a manufacturer and which requires the use of WD equipment, isn't about the receiver as you stated. WD equipment doesn't reduce tongue weight where applied, and it doesn't put less stress on the receiver (it adds a bending moment), so it is illogical to say that adding WD equipment and thus raising the rating is due to the receiver. What is left is that it must be due to the effects of using WD equipment. And that challenges your opinion that if you need WD equipment you need a heavier vehicle. Manufacturers who design and build vehicles disagree with you. WD equipment is a feature designed to increase performance, it isn't just a "nice to have" like heated seats.

... as long as you keep misrepresenting what I said, I will respond without bloviation. ...."Actually, the manufacturers said it."
Manufacturers of what? TV or receiver?

...."isn't about the receiver as you stated."

I never said it was about the receiver alone.
... "I'll say again, IMO, if you're using WD to stay within vehicle specs, another vehicle is in order."🤓
Try it this way...If your using your WD to remove 250lb from the rear axles to stay under their ratings...I...(not you), feel you might do well to consider a TV upgrade.

Bob
🇺🇸

[TouringDan]

Originally Posted by ROBERT CROSS

Try it this way...If your using your WD to remove 250lb from the rear axles to stay under their ratings...I...(not you), feel you might do well to consider a TV upgrade.



Bob

[emoji631]

Bob

If I am over the rear axle weight limit with the WD hitch loose and then I am under the weight limit with the WD adjusted so the rig is level, and I am happy with my TV, this would not be near enough reason for me to replace my TV. I would carry less stuff in order to meet the rear axle requirement, but replacing my 2008 Tundra would not be an option that I would consider. That’s how I look at it.

Dan

[ROBERT CROSS]

Dan,

You are not over WO WD...are you?

Bob
🇺🇸

[TouringDan]

Bob

Definitely not over with my Tradewind, so this is not a problem.

However, I have a 95 34’ and this may pose a problem. It is on the back burner though. I won’t tow it if I am over the axle limits, but I will attempt to meet the axle limits any way I can. For example moving stuff from the bed to the trailer, removing my bed cap, etc. The very last solution would be replacing my 08 Tundra.

Thanks, Dan

[ROBERT CROSS]

Dan,
You may be surprised with the 3 axle 34', the TW may be very close to the 25'. 🤔

Bob
🇺🇸

[TouringDan]

Originally Posted by ROBERT CROSS

Dan,

You may be surprised with the 3 axle 34', the TW may be very close to the 25'. [emoji848]



Bob

[emoji631]

Bob

I did weigh the 34’ when I brought it from Michigan 5 years ago before I put it away. The trailer was empty. The rear axle weight was 3,520 lbs, 580 lbs under the limit of 4,100 lbs. The truck weight was 6,660 lbs, 240 lbs under the GVWR of 6,900 lbs. it looks like this will be the biggest challenge. These weights were measured with the Hensley WD hitch connected.

Dan

[jcl]

Originally Posted by ROBERT CROSS

Ok that's cleared up...all the concern related to receiver ratings not TV, axle or payload.

Bob

This is where it started. I disagreed with this, and said that this particular point was about the TV rating. Accessing the rated tow capacity of some vehicles comes with requirements that one use WD equipment. If one uses a load carrying hitch (referred to by others as a dead weight hitch) then the tow rating is lower, or the rated tow rating is not available, whichever way you want to look at it.

Originally Posted by ROBERT CROSS

"Actually, the manufacturers said it."
Manufacturers of what? TV or receiver?

Tow vehicle. Ford was the example I provided.

Originally Posted by ROBERT CROSS

...."isn't about the receiver as you stated."

I never said it was about the receiver alone.

The receiver is what you stated it was about. See the first quote in this post.

Here is the basic problem IMO:

A certain tow vehicle is rated by its manufacturer with multiple tow ratings, depending on how it is hitched. With a load carrying hitch (non WD) it has a certain tow rating. By using WD equipment, the TV now has a higher tow rating. That is in the Ford towing guide. It applies to multiple F series pickups, up through the Super Duty models.

Let's see what things we agree about re the hitch setup, WD or not. There is a certain tongue load, before one hooks up the WD bars. Now set up the WD. Do we agree that the tongue weight hasn't changed? The downward load on the receiver is the same. The effect of the tongue weight has changed, but not the tongue weight itself. There is an additional bending moment applied. Are we in agreement?

If so, to assume that the receiver rating is the basis of the concern doesn't make sense, at least to me, because the WD equipment applies additional forces to the receiver, not fewer. Yet the TV manufacturer rating with WD is higher. Why would the same receiver with lower forces applied to it be rated to a lower capacity?

Following on, if the receiver isn't the governing factor as to why a non WD setup has a lower tow capacity as specified by the tow vehicle manufacturer, on a specific vehicle, then we must assume that it is the effect of the WD that is the issue, or in this case, the benefit, as it allows one to access the rated towing capacity.

Seems to me it is all about the tow vehicle, and not the receiver. Back to the first quote, you said it wasn't about the TV, axle, or payload. We don't know which of those TV factors it is about. Could be rear axle rating, could be dynamic stability, those are the first two that come to mind. But is isn't about the receiver. I had a vehicle with a certain tongue load and tow capacity rating, and the figures provided by the TV manufacturer were the same for the WD and non-WD (load carrying) setups. That was likely about the receiver, because using WD didn't allow a higher rating, so the strength of the receiver was flagged in my mind.

Originally Posted by ROBERT CROSS

... "I'll say again, IMO, if you're using WD to stay within vehicle specs, another vehicle is in order."

And therein lies the problem. Thinking that WD is just icing on the cake, that it is a nice to have. Some vehicle specs require WD equipment. The TV manufacturer effectively derates the published tow capacity if one doesn't use WD equipment. In this case, the rated towing capacity of some F series pickups. If one has an F350 and doesn't want to use WD equipment, should one consider a heavier vehicle? Or is the WD equipment simply a fundamental part of the hitch setup?

You didn't respond on the SAE receiver class spec. Do we agree that perhaps it is imprecise, given the examples quoted, particularly the use of Class V which is a non-existent class? (I think that is a straight fact, to use your quote, unless there is a new version of the SAE standard that now includes Class V)

[ROBERT CROSS]

Originally Posted by TouringDan

Bob

I did weigh the 34’ when I brought it from Michigan 5 years ago before I put it away. The trailer was empty. The rear axle weight was 3,520 lbs, 580 lbs under the limit of 4,100 lbs. The truck weight was 6,660 lbs, 240 lbs under the GVWR of 6,900 lbs. it looks like this will be the biggest challenge. These weights were measured with the Hensley WD hitch connected.

Dan

Dan
Appears that pulling and handling will be the telltale.
Keep us posted.


Bob
🇺🇸

[ROBERT CROSS]

Originally Posted by jcl

This is where it started. I disagreed with this, and said that this particular point was about the TV rating. Accessing the rated tow capacity of some vehicles comes with requirements that one use WD equipment. If one uses a load carrying hitch (referred to by others as a dead weight hitch) then the tow rating is lower, or the rated tow rating is not available, whichever way you want to look at it.



Tow vehicle. Ford was the example I provided.




The receiver is what you stated it was about. See the first quote in this post.

Here is the basic problem IMO:

A certain tow vehicle is rated by its manufacturer with multiple tow ratings, depending on how it is hitched. With a load carrying hitch (non WD) it has a certain tow rating. By using WD equipment, the TV now has a higher tow rating. That is in the Ford towing guide. It applies to multiple F series pickups, up through the Super Duty models.

Let's see what things we agree about re the hitch setup, WD or not. There is a certain tongue load, before one hooks up the WD bars. Now set up the WD. Do we agree that the tongue weight hasn't changed? The downward load on the receiver is the same. The effect of the tongue weight has changed, but not the tongue weight itself. There is an additional bending moment applied. Are we in agreement?

If so, to assume that the receiver rating is the basis of the concern doesn't make sense, at least to me, because the WD equipment applies additional forces to the receiver, not fewer. Yet the TV manufacturer rating with WD is higher. Why would the same receiver with lower forces applied to it be rated to a lower capacity?

Following on, if the receiver isn't the governing factor as to why a non WD setup has a lower tow capacity as specified by the tow vehicle manufacturer, on a specific vehicle, then we must assume that it is the effect of the WD that is the issue, or in this case, the benefit, as it allows one to access the rated towing capacity.

Seems to me it is all about the tow vehicle, and not the receiver. Back to the first quote, you said it wasn't about the TV, axle, or payload. We don't know which of those TV factors it is about. Could be rear axle rating, could be dynamic stability, those are the first two that come to mind. But is isn't about the receiver. I had a vehicle with a certain tongue load and tow capacity rating, and the figures provided by the TV manufacturer were the same for the WD and non-WD (load carrying) setups. That was likely about the receiver, because using WD didn't allow a higher rating, so the strength of the receiver was flagged in my mind.



And therein lies the problem. Thinking that WD is just icing on the cake, that it is a nice to have. Some vehicle specs require WD equipment. The TV manufacturer effectively derates the published tow capacity if one doesn't use WD equipment. In this case, the rated towing capacity of some F series pickups. If one has an F350 and doesn't want to use WD equipment, should one consider a heavier vehicle? Or is the WD equipment simply a fundamental part of the hitch setup?

You didn't respond on the SAE receiver class spec. Do we agree that perhaps it is imprecise, given the examples quoted, particularly the use of Class V which is a non-existent class? (I think that is a straight fact, to use your quote, unless there is a new version of the SAE standard that now includes Class V)

jcl

You won't change mine and I won't yours...accept it.

🤔...think of all the time wasted tapping on the keyboard stroking the ego.

Sweet Streams

Bob
🇺🇸

[jcl]

Originally Posted by ROBERT CROSS

jcl

You won't change mine and I won't yours...accept it.


Bob

I fully understood that going in. I wasn't attempting to change your mind. The info was more for other readers who were following along.

I don't consider it wasted time, it is interesting and cheap entertainment.

Have a great day!

Jeff

[Gene]

Originally Posted by jcl

Weight isn't just transferred to the TV front axle, and off the TV rear axle, it is also transferred to the trailer axle(s).

Add in the weight of the WD equipment to total weight, but also consider that the measured tongue weight will change because you are measuring it in a different location from the trailer axle centreline, since WD equipment adds length here.

Yes to paragraph 1. I didn't mention it because the issue was about the truck payload.

Sure to Paragraph 2. I am guessing that it doesn't make all that much difference although I'm sure there are exceptions. Maybe I'm wrong. Most people can't figure it out (ask people what a "moment arm" is, a term I vaguely recall and cannot explain very well) I applaud your desire to add engineering facts, but making them understandable is very hard. The 1/3—2/3 weight distribution rule is always wrong if you do the math, but it sure is simple for people who are just trying to get it right. When I was working, I tried to explain stuff I knew from my profession and people looked at me with glassy eyes and I suspected they didn't get it—it is hard to make it simple enough and still explain it correctly. About a decade ago someone posted the formulae to figure out all this. They looked pretty with Greek letters and weird symbols.

Some years ago people on the Forum were continually saying to discount all weights by 20% so you would have a margin of safety. Some of us questioned where that "rule" came from and please justify it. I don't recall anyone ever justifying it and eventually it got forgotten (I expect it will show up again or is quoted on other threads I haven't read). I think it good not to max out mechanical things, but sometimes the manufacturer has already built that in—in my experience Toyotas are real good at that. Before the SAE ratings came out (maybe 5 or more years ago), Toyota was the same or pretty close to them, while other manufacturers had to lower their ratings much more and at least one ignored them. I haven't paid much attention to tow weight threads for a while, so maybe I got that all wrong. If so, I'm sure I'll hear about it.

I guess we won't have a cage match between jci and Bob.

[Shazam]

I started this thread with a question about my Tundra. Let me switch tow vehicles and ask for help interpreting these new weights.

TV- Yukon XL - ratings
Front axle 3600
Rear axle 4400
Max trailer towing 8000
Payload 1551
Curb weight 5775
GVWR 7500

Cat scale weights
Steer axle 3020
Drive axle 4940
Trailer axle 5920
Gross axle 13880

We just completed a 4100 mile trip to Colorado. The Yukon XL with Equalizer WD hitch performed well yet. I am interested in thoughts.
Thanks

[rmkrum]

Need to push a bit of weight off the rear axle somehow. It’s a bit overloaded. Maybe a bit mire weight distribution.

[JJTX]

Originally Posted by Shazam

I started this thread with a question about my Tundra. Let me switch tow vehicles and ask for help interpreting these new weights.

TV- Yukon XL - ratings
Front axle 3600
Rear axle 4400
Max trailer towing 8000
Payload 1551
Curb weight 5775
GVWR 7500

Cat scale weights
Steer axle 3020
Drive axle 4940
Trailer axle 5920
Gross axle 13880

We just completed a 4100 mile trip to Colorado. The Yukon XL with Equalizer WD hitch performed well yet. I am interested in thoughts.
Thanks

Looks to me like you have too much weight on the rear axle. But remember that includes you and your 'stuff' too.

[Shazam]

Forgot to mention- AS is a 25FC GVWR- 7300

[Halford1]

Originally Posted by Shazam

2011 Tundra - GVWR= 6900
2015 25FC GVWR= 7300. Dry weight is 5700.
Plan is 4-5 hour trips at essentially no elevation (middle Georgia)

We will only be adding about 600 pounds of gear max.
Can I tow with this Tundra ?

You already know the answer. Some of us would not give a good answer and enable you to damage your truck in process. you saw the math clearly. Ignore the dry weight and focus on the max weight "wet". No matter how flat the half state is (I used to live in GA and know that N GA would kill your TV).

The max weight tow is also for safety of your family in your TV and also the vehicles beside, front and back of you on road. Going over is not good for braking.